Pirates lag in ABS challenge success, a sign their early adjustment has not fully clicked

Major League Baseball’s Automated Ball-Strike (ABS) system has changed how teams think about close pitches, and the Pittsburgh Pirates are finding that adaptation can be uneven. In a team-focused discussion from MLB, the Pirates were identified as the only club sitting in the bottom three for challenge percentage in two key areas: behind the plate and in the batter’s box as the season reaches the 75-game mark.

ABS, introduced to reduce human variation in called balls and strikes, also comes with a challenge ecosystem. Each side has to decide, quickly, when a pitch that is most likely to sway an at-bat is worth using a replay challenge on. Those decisions are not just about a single pitch, but about managing risk across an inning, a game, and the larger swing of a series.

According to MLB’s look at Pittsburgh’s early results, the Pirates rank in the bottom three for challenge percentage both defensively (where the catcher and game plan meet the umpiring call) and offensively (where batter outcomes can be affected by what the system is indicating). In practical terms, that points to a gap between when the Pirates believe a call should be different and when ABS data shows they should have left it alone.

The challenge percentage metric matters because it affects more than just whether a single protest is won or lost. When teams challenge frequently without landing, they can end up training themselves into a lower-confidence decision loop, while also risking the depletion of the challenge opportunities that can be crucial in later leverage situations. Conversely, teams that are too conservative can carry games with preventable strike/ball swings that never get corrected.

What makes the Pirates’ profile notable is that ABS is still new for every organization. MLB’s framing emphasizes that every team is working out how to use ABS to its advantage, which means there is a learning curve built into everything from the catcher’s pre-pitch routines to the manager’s in-game confidence level and the replay staff’s interpretation of which pitches are “challenge-worthy” under ABS.

For Pittsburgh, the immediate takeaway is process. MLB’s report suggests the club is working through how to tighten alignment between the staff’s instincts and the system’s underlying calls. That could include more calibration time in bullpen and in-game communication, clearer thresholds for what pitch types are most likely to produce meaningful differences, and adjustments to when the Pirates choose to challenge versus when they choose to let the plate appearance reset.

Looking ahead, the early season context matters: with ABS now established across MLB, teams that improve their challenge decision-making tend to see better alignment between strategy and outcomes. For the Pirates, the next step is to move off the bottom-three challenge-percentage footing behind the plate and in the batter’s box, and then see whether that improvement translates into steadier inning management and fewer costly, preventable changes in count and plate-appearance trajectory.

Until a fuller, end-of-season statistical snapshot is available, Pittsburgh’s situation should be viewed as a midseason adjustment problem rather than a single-game storyline. The Pirates appear to be searching for the right balance in how they apply ABS information in real time, and their progress will likely show up most clearly in whether their challenges become more selective without becoming overly timid.