ABS, or MLB's automated balls and strikes system, has been a long time coming. Baseball players, managers and fans are tired of relying solely on the human element to determine close games. To be clear, ABS will not completely eliminate mistakes from home plate umpires, though it will put the ball in the players' court. Players will have the opportunity to challenge close balls and/or strikes that go against their better judgement. In that sense, the rules are quite simple.
Per MLB's official announcement, these are the ABS rules you need to know:
- Each team will get two challenges and can keep them if they're successful.
- Challenges can only be initiated by a pitcher, catcher, or batter, and the request must come right after the pitch.
- To signal a challenge, the pitcher, catcher, or batter will tap his hat or helmet to let the umpire know.
- No help from the dugout or other players on the field is allowed.
- In each extra inning, a team will be awarded a challenge if it has none remaining entering the inning.
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MLB umpire CB Bucknor had a miserable ninth inning in the Braves-Nationals game
While the likes of Joe West and Angel Hernandez have long since retired, CB Bucknor remains one of the most influential veteran umpires in today's game. Bucknor has worked as an umpire in the National League since 1996, and league-wide since 2000. Even though he wasn't behind home plate for the Nationals victory over the Braves – a game which ended Atlanta's 10-game winning streak – he made a good case as to why ABS was the right idea, and also proved it alone won't solve MLB's primary concern with the human element of umpiring.
Bucknor, who was the first-base umpire in this game, missed two calls in the bottom of the ninth inning. The first was egregious, while the second wasn't particularly close. On the first missed call, Ronald Acuña Jr. was called out on what should've been an infield single. The play was overturned thanks to replay review. On the second play, Drake Baldwin was called out on a dribbler past the pitcher's mound. You'll never guess what happened next, as it turns out Bucknor got the call wrong again.
CB Bucknor missed the last two calls of the Braves-Nationals game today but luckily we have instant replay. pic.twitter.com/YVhLMy3AVa
— Codify (@CodifyBaseball) September 24, 2025
What CB Bucknor's missed calls say about ABS in the majors
If Bucknor's missed calls tell us anything, it's that there is little more MLB can do to ensure umpires get the calls right. They have a replay system in place, and unless they fully replace umpires as a whole and add chips into the ball/basepaths (don't get me started on how that would work, look no further than the English Premier League), we will continue to have stoppages of play to correct the work of human error.
In this case, Bucknor's flaws were inconsequential. This is a game that won't matter for either the Braves or Nationals, as both are well out of the postseason race in the National League. However, if Bucknor is asked to ump in the postseason, he'll have plenty of eyes on him, and for good reason.