MLB's First ABS Season: 54% Overturn Rate, Reds Lead, Dodgers Lag

Key points

• Overall, 5,686 out of 10,557 challenges were overturned, yielding a 54% success rate.
• Fielders had a 58% success rate on 5,792 attempts, outperforming hitters who succeeded 49% of the time on 4,765 attempts.
• The Cincinnati Reds achieved the highest net run gain at +16.8, while the Cleveland Guardians finished last at -13.4.
• The Los Angeles Dodgers ranked 26th with -8.5 net runs, and the New York Yankees ranked 16th with -2.1 net runs.
• Shohei Ohtani was the second-worst batter in defensive challenges, losing 5.5 projected runs, while Jose Altuve was the most successful hitter with 5.6 projected runs gained.
• The system impacted the postseason, as J.T. Realmuto's successful challenge in Game 2 of the NL Wild Card series ended the game.

Background

The Automated Ball-Strike (ABS) system was introduced for the 2026 MLB season to replace traditional human umpire calls with technology-driven decisions. This marked the first full season where teams could challenge these calls, leading to significant statistical variations in success rates across the league.

How outlets are covering it

AP News highlighted the overall 54% overturn rate and the learning curve for teams. Bleacher Report provided detailed team rankings, noting that the Cincinnati Reds were the most successful while the Cleveland Guardians were the least. ESPN's source was inaccessible due to a 403 error, so no additional perspectives could be synthesized from that outlet. Bleacher Report also emphasized the disparity between fielding and batting challenge success rates, with fielders performing better.

Why it matters

The ABS system's debut has significantly impacted game outcomes and team strategies, as evidenced by the high overturn rate and the negative net runs for several playoff teams. This shift may influence future rule changes and team preparations in MLB.

What to watch

Teams will likely adjust their challenge strategies based on the 2026 data, focusing on improving batting challenge success rates. MLB may review the system's impact on game flow and fairness before the 2027 season.