Mlb Approves Robot Umpires for 2026 as Part of Challenge System
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MLB is introducing automated ball-strike (ABS) umpiring as part of a challenge system in 2026, sparking discussion about the impact on the game and its traditions.
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But now when the viewers can see the pitch in 1000fps 8K slow motion, they expect better from the umpires. The entire premise of sports relies on the assumption that the rules are adjudicated correctly.
Part of the soul of the game is learning the umpire's particular strike zone and adjusting accordingly.
I'm with OP. Fun is being replaced by data.
I also just say watch every angle at full speed for those types of replay, no slow-mo. Keeps the magic, but let's you correct egregious calls.
Everyone knows the tie goes to the runner but it's not an official rule apparently.
The soul of baseball is in the squishy parts. Quantifying the life out of it is not a good idea.
I don't hate the challenge system as much as I would an entirely-automated strike zone - and I'll probably appreciate the occasional corrected call, and the game-within-a-game of when to spend your challenges - but it's all of a piece with the general flattening of baseball. The DH, and now the universal DH. Interleague play. Balanced schedules. Three true outcomes hitters. Outlawing certain defensive positioning. Maniacal pursuit of spin-rate. Manfred runners. All of these eliminate elements of the game that made it more interesting - at least from this Old Man's perspective.
(As counter-examples: I like the pitch clock, and I'm OK with enlarging the bases; those increase the premium that accrues to specific skills, and heighten the stakes of particular situations. Those are the directions in which positive changes should point.)
Review systems for cricket and tennis seem to have enabled more crowd involvement and anticipation in the lead up to a decision being revealed.
Awful calls need to be struck from the game and this should do that. Tonight my Blue Jays had a double taken away on a foul call and a ball 2 inches off the plate called a strike in the same at bat with the bases loaded. Between this and the horrible reviews last week it feels like the fix is by MLB to keep us from winning the division.
Unlike tennis where in and out have always been strictly defined and we just didn't have the technology to enforce it, baseball has always involved the human element to the strike zone and some umpire judgement on whether the pitcher hit the spot or just got lucky and what a given batter's zone is. I want some of that to stay, with catchers holding game-long discussions about the zone with umpires, and batters having their own sense of the zone.
I don't want full automatic balls and strikes, so I like the challenge. There is some new strategy on when to deploy it and who can be trusted to recognize a missed call. It leaves some room for a pitcher and catcher to work a corner over a few innings to expand little by little.
I only hope they don't switch to a system entirely governed by an automated strike zone without umps.
It'll allow the "human element" many players still prefer along with some level of framing, while keeping umps honest (there are way too many egregious calls these days).
Then along comes sports betting and they basically have no choice but to use robots.
It’s sad to me how much sports betting changes sports. When I watch, I wonder if the referee has accepted a bribe every time a call is a little funky. Considering the millions of dollars riding on every play, some of them must have taken some money at some point.
He oversaw the last collective bargaining agreement in 2021/22. It’s expiring this year. That’s one of the reasons why the rule change is going through now.
I won’t deny that sports betting could be a factor, but Manfred wants faster more engaging baseball. That’s been his stated goal for a long time as he worked through rule changes.
Why would the owners? “Good will” has never worked in MLB negotiations and I don’t see that changing.
What has not changed since before both of those timelines is baseball umpires have a union[0].
Maybe, just maybe, their union fought the introduction of this to the bitter end.
0 - https://en.wikipedia.org/wiki/Major_League_Baseball_Umpires_...
We've come a long way from the black sox and Pete Rose being banned for life over gambling
https://en.wikipedia.org/wiki/Black_Sox_Scandal https://en.wikipedia.org/wiki/Pete_Rose#Permanent_ineligibil...
I don't love sports betting in general, but I really hate betting on short term events like specific pitches or a strikeout. There is way too much incentive to fix.
Their rise and market is so large that only 5% of sports bets aren't placed through one of these apps.
Not sure if I agree with OPs take though. It might just be that baseball is a traditional, conservative game and they are hesitant to change it. maybe that's why they're just using robo umps for challenges, and not for every pitch, which would be easy to do and would further the all-about-betting theory.
As a Cubs fan, I still read that and thought, "So say we all."
As someone that has been a soccer (makes me throw up a little to say that word), ahem, football referee, I can tell you that not all funky calls are because the ref is rigging the game. Sometimes, you just miss stuff. Sometimes, you just see it differently. Sometimes, you just fuck up. Yes, a few have definitely admitted to taking bribes. Granted, I never was an official on anything professional. Even still, you'd make a call and the fans of the team you call a foul against all go crazy. Two minutes later, you make a call going the other way, and the other fans go nuts. I always laughed when I'd hear comments about needing glasses and "how much they pay you". You can't make 100% happy, ever. Fan is short for fanatic, and it's very appropriate.
To that end, I'm surprised that MLB never introduced replays. Cricket has replays and even have microphones that they watch the waveforms to see if there was contact or not.
I just watched the replay, and I'm convinced VAR would rule it offside. So the hand of god would be irrelevant. The AR on the far side of the pitch is just out of frame at the crucial moment, so he was clearly behind the play. That's a position you never want to find yourself as an AR. I always found the AR role much more demanding than the referee. Keeping that offside line is difficult at best and nearly impossible if you're 30+ something trying to keep up with fit professional athletes in peak fitness in their 20s. Now, after that call was blown, again due to the framing, it is hard to see where the ref was looking. You can see his last position easily 30 yards from goal while Maradona makes contact about 8 yards from goal. There are at least 15 players in between the ref and the play at that point. Also, a very telling thing is that there was no conversation between the AR and the ref. On contentious plays, you'd see the ref back peddle to the AR (never take your eyes of the pitch) and have a chat about who saw what. I don't know if the ref crew had radios back in 1986, but the fact that the ref did not think it was worthy of a chat with his AR who would have had a different angle to view it says a lot about the ref's thinking. If the AR had seen it and wanted to chat with the ref, he would have stood still with his flag raised. If he felt the goal was good, he would keep his flag down and make a little run up the touchline towards midfield. The linked YT footage is cropped (pushed in I assume to remove any network branding) so the AR is out of frame. In the very last replay with the camera from behind the goal line on the near side, you can barely make out the AR but it cuts before he signals. My guess is he turned and ran up the touchline. Again, it is obvious he is out of position behind the play, so his view was more than likely blocked.
At the end of the day, if you can't absolutely positively tell that something happened, you pretty much let it stand. Just because all of the defenders raised their arms does not make it offside. There's only one person that can tell you that, and he couldn't make the call so had to let it go. There's no way the ref was going to call offside. The one thing they do teach you is that if you're unsure, make a call and make everyone think you're sure. Just own it, and move on. Never had to do that for a goal, but there's plenty of times I don't know who was last to touch the ball before it went out so you turn to the AR to get a clue. It's always fun when they shrug. You just pick on what you think you saw and just confidently rule that way. It's a damn throw, just put the ball back in play. Corners vs goal kicks are more risky, so always safe to rule for the defense with a goal kick. Never want a team to score on a bad call from a ref. Of course, none of that is ever taught to a ref...in those terms.
However, I think if you use the enhance feature to zoom into the ref's back pocket, you can see the cash he was paid to let it happen /s
But yeah the objection IIUC was not over offside despite what the announcer says. He realizes at the end that it's an apparent handball. "At what point was he offside ... or was it a use of the hand that England are complaining about?"
> ... back peddle to the AR (never take your eyes of the pitch)
Is this because of the risk of violence from the players?
that's part of it, but just in general you can't be in control if you can't see it.
> But yeah the objection IIUC was not over offside despite what the announcer says. He realizes at the end that it's an apparent handball. "At what point was he offside ... or was it a use of the hand that England are complaining about?"
wow, i wrote a whole diatribe about offside, and that had nothing to do with your comment <face-palm>
In the modern game, VAR would wind the goal scoring play to the beginning of the play to see if there was anything missed. They would look for the first reason to stop the play. In that case, the offside would be seen first and the goal would be disallowed for that.
Back then, the offside was missed by the AR so play continued. Even the England players didn't complain about the offside. They were complaining about the hand ball. It should have been the more obvious thing for a ref to see.
If you see how the players are screaming about the hand ball, it is with the hand raised over the head which does look like what every defender does to imitate the AR raising the flag. However, you see the other hand comes up to slap the wrist indicating they want the foul for handling the ball. To be fair, from the commentator's perspective, the offside was clearly visible. It's only natural to think that's what everyone would be complaining about. It is possible that even the ref was looking at his AR waiting for the flag to go up and wasn't even looking at the play and missed the hand in his befuddlement at the no offside call
I'm sure that the offside law has been "refined" between 1986 and now, but this is the law as of today and there is a huge difference between touches by teammates and defenders:
https://www.theifab.com/laws/latest/offside/#offside-offence
So yeah, officials do influence play and frankly I think it's a good and healthy thing for the sport overall when they do. In the case of balls and strikes I support automated calls because that's very simple (the ball is either in the box or not, and we can hem and haw about how we define the box during the off-season) and the infra to do it is already in-place. But in difficult, judgment-call situations (to take american football as an example, what's the actual, objectively-defined line between a corner getting handsy and defensive pass interference?) I not only think humans are necessary despite their biases but because of them. Obv bias in favor of any one team or style of play needs to be rooted out but the way that officials actually call games, even when it varies from the rules, seems to actually benefit the sport, the athletes and the fans in a lot of unexpected ways.
For other situations of officials influencing the game, the big one is how often they use their whistle to stop play. If they are calling ticky tacky fouls, the game slows down to nothing but restarts and there's no real flow. In youth matches, parents love it when the ref protects their precious little angel. Players HATE it. A ref that players like are the ones that let the game play. If two players are both strong in their fight for the ball with some possible pulling/holding equally from both sides, let it go. Let the stronger player win. If one player obviously is using the dark arts to gain unfair advantage, sure stop the play.
As far as blow out games with the stronger team getting more penalties, it could be a much more simple explanation as the ball just spends more time in the area which raises the likelihood of a penalty occurring. A game with back and forth will see less penalties. A game where one team is putting constant pressure on the goal is much more likely for a defender to make a mistake. Just like the awarding of an own goal. They only happen because the attacking team was putting pressure where an own goal could even be possible.
This may be specific to hockey but that's the game I care and know most about: as a rule if there's a blowout it's usually the defenders taking penalties. Whether it's a blowout because defenders are taking penalties, leading to a lot more time at a disadvantage or defenders are taking penalties because its a blowout, they're getting dominated and they can't defend without breaking the rules is difficult to tease out objectively but anecdotally it's the latter. Nobody's faster than you if you grab them by the jersey. No one is stronger than you if you trip them with your stick. You try doing it legally at first but if that doesn't work then you try getting away with doing it illegally. Whereas if you're just absolutely imposing your will on a team anyway why bother grabbing a stick that isn't lifting yours up anyway, or holding onto the jersey of someone who's already behind you? But the data reveal the opposite: the team in the lead tends to be more likely to take a penalty and the theory is that the refs just assume they can afford it and it won't affect the outcome or create an appearance of impropriety. But a tickytack holding call against a team that's already down by 3 feels like piling on at best and intentionally influencing the game at worst, and that's why officials tend to avoid it.
https://en.wikipedia.org/wiki/Instant_replay_in_Major_League...
But replays weren’t allowed for balls and strikes, the subject of the new system.
the above is from https://en.m.wikipedia.org/wiki/Ron_Luciano 's book but wikipedia doesn't mention it. Though it was 40 years since I read the book so maybe I don't remember right?
I think it makes the game human. also football with replays on ever play is too slow.
My point is the existence of the question...It's possible that someone could wager $10,000 on some player striking out and give the ump $5k for making sure the slightly-outside ball is a called strike. And with all $150,000,000,000 sloshing around sports right now, we'd be foolish to think that _never_ happens.
I have no idea how many calls are intentionally blown for money, but I'm confident it's not zero.
It went from having to go out of your way to locate and operate with a bookie who had little away with the sports organization to... Pulling out your phone and tapping a couple of buttons, paying a legitimate business who can then apply enormous legislative and financial pressure directly against the teams with billions in backing.
It has dramatically changed the state of gambling, sports, and the businesses around them.
There are literally countless incidents of people cheating. So my suggestion is to hope it doesn't happen but also just avoid making bets if you are not comfortable with the fact that you may lose.
The ability to bet on short term individual events (such as a single pitch) means that even a single pitch, otherwise nearly inconsequential, can be abused.
It’s sort of been swept under the rug even though it was initially reported on
Professional NBA referee betting on games he was refereeing - what a joke
I realize that it's an objectively ridiculous thing to have strong feelings about, but boy do I hate it :D
The quest for eternal optimization is exhausting.
The primary use case is the glaring wrong calls. 1/2 a ball in/out of the zone called wrong. The batter/catcher/pitcher have to do the challenge, so, ideally, the “obvious” ones should be readily challenged.
But the close calls, the squeakers, the players have very little time to make the challenge and we saw lots of failures in Spring Training this year.
So, there’s still a lot of judgement and uncertainty to deal with. And don’t forget the the Umpires have been being evaluated based on the automated box for years. They review each game and the Umpires performance. It’s just not had actual game impact before.
I have no doubt that there will be some important, game impacting “bad calls” going forward. It just that there will be fewer of them. Also be interesting to see if the get extra challenges in the post season/WS games.
The problem is we have more and more technology (camera angles, first down markers, strike zones, HD and 4K resolution, etc) that make it easier to see errors after the fact.
Not using technology to get things right starts to feel like dereliction of duty by the leagues as evidence of errors pile up.
I accept the "human element" but I wouldn't say I like it. I do think umps having their own strike zones is one of the better instances of human element, though (so long as they're consistent).
If you want a human element this is just using it as a challenge system. So the players have to have a good eye to decide whether an ump was right or wrong and they can’t get help from anyone else to decide to challenge a call.
Arguing about calls when we were watching blurry slow-mo on CRTs isn't the same as when we're watching crystal clear 4K.
Even with a challenge system as you describe, you still have potential for an ump missing calls that are obvious to everyone watching on TV.
Being able to challenge is good, sure, as a bare minimum, but it's very arguable that players shouldn't have to.
Guaranteed perfectly-called games every time.
Doesn't sound particularly fun to me, but to each their own.
Is this even a serious argument? Come on. I would almost think you were trolling, conflating the performance of the umpires vs the performance of the players, were this not HN.
Initially I was going to argue that that's a silly thing to prioritize in a game, but it's a matter of taste and I'm not going to tell you what to like or not. It's not like you said that you liked arguing with your friends or something.
In all seriousness though, sure, everyone wants a fair game, but there's limitations. For instance, I only watch minor league baseball, and it's not because they got the pitch clock and ABS first, it's because the teams aren't completely optimized like the majors, and the game isn't as refined - it's closer in spirit to the first game of baseball ever played.
Frankly, I'd rather watch a pick-up game without an umpire if it weren't weird (and I could get a beer and some hotdogs).
Long story short (too late), baseball's a lot of different things to a lot of different people. The stats, the camaraderie, the competition, or the culture around the game itself. If you prized a game going off like clockwork, I couldn't fault you, even if that doesn't factor into my love of the game at all.
https://x.com/UmpScorecards/status/1917951876349284772
At the time, every umpire had their own strike box, and I loved it! It added variance to the pitches and swings each game. Some batters would turn their head and confirm with the umpire where one edge of the box was when they called a strike (and others would silently curse without turning their head haha)
I think players liked arguing with the umps, too.
The last frontier of ejections will probably be discretion when players get plunked at the plate.
:raises hand:
Granted, I didnt grow up a baseball fan and am only now getting into through my kids being in baseball, but coming from less "traditional" sports like basketball I really dont care for the whole spectacle side of baseball. Even in little league you get way more arguing with umpires from coaches and parents alike and its all so juvenile.
I guess I reconcile those positions because I follow the "top-flight" sports I enjoy (in part) as long-running, interconnected narratives. Some of that's on the technical level - like, "this guy played this way last time; how will he approach a similar situation this time" - but it also embraces the personalities involved. The three managers I mentioned were outsized characters in the baseball "story", and I enjoyed their roles - as did they. Each was well aware of the theatricality of their actions, as were the umpires, and there were very few genuine hard feelings.
Earl Weaver, in particular, sometimes ran onto the field bellowing something like "that was a good call! But you gotta run [eject] me here, 'cause I need get them [players / fans] into the game" (though doubtless with more profanity than is appropriate for this forum). Then he and the umpire would yell at each other for a bit, until he departed in (mock) high dudgeon. That was kayfabe, but not purely for the sake of spectacle. He believed - and there's research since that backs up his intuition - that getting his team and fans fired up would be a strategic advantage.
None of that applies / should apply to amateur competitions. I also respect your point of view if you don't watch professional sports from same the angle that I do.
I dont think baseball does a good job of being honest about umpires blowing calls, and to fight the perception of being wrong umpires lean _way_ to the other side to the point that if a batter is even suspected of questioning a call they are ejected. Then, sure, I dont see a problem with the arguing because what else can you do. Its a tight rope, and I dont think they've walked it well. It does feed into the lower leagues though, with completely different relationships (volunteer umps and no replay review), but the same antics.
Instead of doing the hard right thing, baseball does something easier that will be worse for the game. Faugh.
The game will be fine.
Sometimes it isn't really clear, like, if the ball is caught very close to the boundary line, given the size of the field, it can be tricky for the umpire to tell if it was caught over the boundary, representing the difference between the current batsman being caught out (meaning either the next batsman has to come take his place - assuming there are any of the 11 left) or adding 6 runs to his team's tally.
Some of the most memorable cricket games have had such situations.
It also adds some suspense to games as everyone waits on umpires to review data to make their call.
That said. Strike zone height is between 53.5% and 23% of a player’s height. WTFBBQ. That’s a major change, and I don’t understand how it’s going to go with an Ump’s calling the zone — right now a player’s stance can affect the zone height. How will umps assess 53.5% of a player’s height realtime?
Also there’s no excuse for not having full 360 3D representative video for each base. Having some sort of pressure sensor would be useful too.
Better safety features would be useful (like better face protection like the cricket steel grill).
And just more damn cameras for all the edges (like home run or foul lines).
So in terms of volume, this isn't much. In terms of potential effects, it becomes a question of how well players utilize their teams' two challenges (teams retain challenges if they correctly use them, but only the batter, the catcher, and the pitcher can request a challenge).
It all becomes an interesting question in terms of strategies. A catcher when he's batting? Does he want to risk one of his team's challenges as a batter that he might want for his pitcher? A mediocre hitter in a low-stakes situation? Does he want to risk one of his team's challenges? What about a really good hitter in a low-stakes situation? Lots here for teams to consider, and since it's up to the players to decide on a challenge (not managers or coaches), teams will have to determine their approaches such that players can make decisions without assistance.
https://blogs.fangraphs.com/strike-three-lets-check-in-on-um...
If it's not a joke, please realize this doesn't replace anyone and is also not doing anything that's meaningfully "AI".
I'll also note that MLB isn't doing the "replace umpires with software". Teams get 2 challenges to use, and those are adjudicated by robots. The initial call is made by humans and a human has to say "use my finite resource to engage the robots". (I would just make all calls by robot and have a challenge to have humans look at it, but whatever. Baby steps. We know where this is going.)
The NFL uses the same technology to measure first downs now. No more carrying the chains out to measure by hand. But the officials still spot the ball where they think they play ended, so the computer isn't doing anything important. It's just doing the tedious part.
Nobody is losing their job and no fun is being removed from the game.
And at the end of it all, some missed calls get to be corrected.
I saw it in practice a few times this year during spring training games, and it was _fast_. Add to that the fact that only pitchers, catchers, and hitters can request one (no managers holding the game up while the replay room checks on it), and it really won't slow the game down at all.
/something higher tech than banging a garbage can obviously.
They finally replaced you, sir, the ump with a robot.
How long until we have an AI president with an economics degree?