How MLB's New Clock and Shift Rules Have Changed Scoring Patterns in 2025

Major League Baseball's 2023 rule changes — the pitch clock, shift restrictions, larger bases and the tightening of balk restrictions — have now had three full seasons to take effect. The 2025 season's statistical data, released by MLB's central office in November, offer the clearest picture yet of how the changes have reshaped scoring, pace and competitive balance in the sport.

Average game times have fallen from 3 hours, 4 minutes in 2022 to 2 hours, 41 minutes in 2025, a decrease of 13 percent. Scoring per game has risen from 4.28 runs to 4.61 runs, while batting averages on balls in play have climbed from .290 to .303. The changes have been statistically significant across all three seasons.

The Pitch Clock's Biggest Effect

The pitch clock — 15 seconds with bases empty, 20 seconds with runners on — has been the most impactful of the three changes. The average at-bat duration has fallen from 3 minutes, 40 seconds (2022) to 2 minutes, 51 seconds (2025). Pitchers are permitted 30 seconds between batters, down from the 40 seconds that had been the informal pre-clock norm.

The clock has produced unintended strategic consequences. Pitchers with less time between pitches have shown fewer effective pitch mixes — research published in the Journal of Sports Analytics found a 14 percent reduction in pitch-type variability among starters throwing more than 80 pitches. Catchers have also taken on a larger game-calling role, as pitching coaches have less time to signal changes from the dugout.

Shift Restriction Effects

The ban on defensive shifts — four infielders must now play on the infield dirt, with at least two on each side of second base — has produced the most visible on-field changes. Left-handed pull hitters, the primary target of pre-2023 shifting, have benefited substantially.

Freddie Freeman's batting average on pulled ground balls has risen from .217 (2019-2022 average) to .286 (2023-2025 average), per Baseball Savant data. Similar rises have been observed for Max Kepler, Anthony Rizzo and Yordan Alvarez. The overall left-handed hitter BABIP (batting average on balls in play) has risen from .293 to .311.

Base Size and Stolen Bases

The increase of base size from 15 inches square to 18 inches square was expected to increase stolen-base attempts and success rates. The effect has exceeded projections. Stolen-base attempts per game have risen from 0.68 (2022) to 1.41 (2025), a 108 percent increase. Success rates have also improved, from 75.4 percent to 80.8 percent.

The league's all-time stolen-base leader remains Rickey Henderson at 1,406. Active leaders have closed on career-milestone thresholds more quickly. Ronald Acuna Jr., who missed much of 2023 and all of 2024 with an ACL tear, rose from 204 career stolen bases at the end of 2022 to 291 by the end of 2025 — a rate of advancement that would have required roughly seven seasons under the pre-change rules.

The Disabled-List Debate

Injury rates among pitchers have risen since 2023, with many inside baseball attributing the rise to the compressed time between pitches. The MLB Players Association's 2024 injury report noted a 12 percent rise in elbow, shoulder and hamstring injuries among pitchers compared with the 2017-2022 average.

The league has publicly disputed a direct causal link, citing overall improvements in pitching velocity and spin rate as contributing factors. Commissioner Rob Manfred said at an October 2025 press conference that the league was "monitoring the data" but had "no current plan to adjust pitch clock length."

Competitive Balance

The rule changes were expected to level the playing field between traditionally strong and weaker franchises. The evidence is mixed. The 2025 World Series was won by the Los Angeles Dodgers over the New York Yankees — two of the league's highest-payroll teams — in six games. However, the Oakland Athletics, the league's lowest-payroll team, finished with a .500 record for the first time since 2013.

The analytical metric for competitive balance — the standard deviation of team winning percentages across a season — has fallen from .075 (2019) to .063 (2025), a statistically significant decrease. Smaller-market teams, including the Milwaukee Brewers, Cleveland Guardians and Pittsburgh Pirates, have posted .550-plus records at rates higher than any five-year stretch since 2010.

Broadcasting and Ratings

MLB's regular-season television ratings have risen 18 percent since 2022, per MRC Data analysis. The World Series drew its highest average viewership since 2017, peaking at 17.2 million for Game 6 of the 2025 Dodgers-Yankees matchup. The shorter game duration has been cited by broadcasters as the primary reason for improved ratings among casual viewers.

ESPN's new baseball broadcast package, signed in 2023 for $550 million annually through 2028, has outperformed viewership projections. Sunday Night Baseball has averaged 1.8 million viewers in 2025, up from 1.4 million in 2022. The MLB Network and regional sports networks have reported similar gains.

Rule Change Trajectory

Manfred has publicly discussed additional rule changes for 2027 and beyond. The most-discussed idea is a two-strike foul rule that would allow a fourth pitch after two strikes if the batter fouls off the first three with two strikes. No formal proposal has been brought to the MLB-PA collective bargaining table.

The current CBA runs through the end of the 2026 season. Negotiations for the next agreement are expected to begin in mid-2026. Pitch clock adjustments, salary arbitration reforms and expanded draft lottery provisions are likely to be the primary negotiating topics, according to MLBPA public statements.