4 lessons players have learned about ABS

It’s hard to believe, but the 2026 season is almost here, with Opening Night looming on Wednesday.

This season-opener promises to be historic: For the very first time in a regular-season game, players will be able to challenge balls and strikes thanks to the Automated-Ball Strike (ABS) Challenge system, powered by T-Mobile.

On one hand, ABS is new. On the other hand, though, it’s not entirely foreign. The challenge system was used all of last season at Triple-A, and Major League players have used it at Spring Training in each of the past two years. As a result, the vast majority of players have already experimented with ABS, familiarizing themselves with the ins and outs of baseball’s latest innovation.

But what have they learned? Our MLB.com beat writers surveyed their clubhouses and asked players for their opinions on a range of topics surrounding their experience with ABS, in exchange for anonymity.

Here are four of their biggest takeaways.

1. Know how to pick your spots

This may be the most important part of ABS-related strategy: Not deciding what pitches to challenge, but when to challenge them.

“Obviously, you don’t want to be stuck without a challenge and it’s a big call in the ninth, right?” said a player in the AL East.

A number of players learned that the hard way.

“I’m 3-for-4 [in my] career on challenges, but the one that I missed, it was a very emotional challenge in the first inning,” said a pitcher in the NL Central. “It was like, ‘That was so stupid of me. Why would I make that challenge?’”

Teams are only allotted two ball-strike challenges per game (though additional challenges are granted in extra innings). Challenges are lost when the call on the field is confirmed.

With just two challenges to spare, players must be judicious.

“Don’t waste it early,” said a player in the AL East.

Added another AL East player: “If it’s nobody on, nobody out -- [no challenge]. It’s there for something egregious.”

Teams have held meetings to discuss their ABS-related strategy. The Phillies, for instance, are deploying their analytics department to provide best practices for ABS, likely based on the count, number of outs, and inning. They are almost certainly not alone.

As ABS data from the 2025 Triple-A season shows us, challenges really do get saved for the end of the game. But that requires a fair amount of discipline, too.

“There’s some accountability of just knowing yourself, knowing the situation,” an NL Central player said. “You really have to be steadfast in that.”

2. Take the emotions out of it

Recall the anonymous NL Central pitcher above who rued his “very emotional” first-inning challenge. That’s far from an isolated experience.

“People let their emotions determine whether they challenge or not,” said a player in the AL East.

Doing otherwise is easier said than done. For all the talk of “robo umps,” the ABS system does not strip the human element from the game.

“I’ve been there,” an NL Central player said. “You’re struggling at the time and you think, ‘There’s no way that’s a strike.’ You get emotional about it. And it is a strike.”

And in that case, the player would have cost his team a valuable challenge.

But is it possible to hold these emotions in check? Teams have talked openly about this throughout the spring. It’s something that everyone is cognizant of.

“You have to check yourself,” Phillies catcher Garrett Stubbs said. “If you get dinged for close pitches, you’ll start to get [upset] and you’ll want to challenge.”

3. Some pitches are tougher than others

This has a bit to do with pitch velocity, and also a whole lot to do with pitch movement. Any pitch with a combination of plus movement and elite velocity is going to make life difficult on anyone considering a challenge.

“Sinkers are really hard to judge,” said an AL West player. “It’s so hard to tell if the ball nicks the bottom of the zone.”

Added another player in the AL West: “On TV, they’ll be like, ‘Oh, you should have challenged that.’ It’s hard to tell that in real time, as the ball’s coming in at 96 [miles per hour].”

These are split-second decisions, and with only two challenges a game, there’s no room for error.

ABS might also help pitchers and catchers earn strike calls on certain pitch types that previously had a tendency to be missed.

“I miss a lot of backdoor sweepers because they start so far out,” said a catcher in the AL East. “Now, you might get those 50/50 calls.”

Last year, for example, no player/pitch type combination had more pitches in the strike zone called a ball than Framber Valdez’s sinker.

4. Catcher framing will still matter

Over the past decade, a slew of technological innovations have allowed players and teams to properly value catcher framing, a long under-appreciated aspect of the game.

But what does the future of catcher framing look like amid the arrival of ABS? As the players told us above, there’s still a strong human element at play here. ABS is different from “robot umps.” So, catcher framing isn’t going away -- if anything, it may have gotten more nuanced.

“It’s different,” said one catcher in the AL West. “Instead of trying to trick the umpire, sometimes you try to trick the batter into thinking a strike is a ball, so that they use the challenge.”

That’s right. ABS will introduce a whole new layer of strategy to the art of catcher framing.

Many of the players surveyed in this poll view ABS as more of a catcher’s thing than a pitcher’s thing; most pitchers trust their catchers to challenge a call at the right juncture of the game. Adding to that, catchers are the ones with new strategies at their fingertips, too: Think of a scenario where a catcher uses his framing skills to goad the hitter into burning a challenge on a pitch that really isn’t all that close.

“But it’s hard to do and doesn’t happen too often,” cautioned an AL West catcher.

At least to start, here’s something that could happen more often: a bit of friendly fire.

“Catchers are so good at framing that, as a pitcher, you can’t tell when you’re on the mound where the ball actually crossed the plate,” said a player in the NL West.

Remember that a number of players surveyed believe that pitchers should never issue a challenge, mainly because the catchers are simply too good.

“A lot of catchers make everything feel like a strike,” said a player in the AL East.

Framing isn’t going away. It may just look a little different.