Since the 2020 MLB season, relief pitchers must face a minimum of three consecutive batters (or complete an inning) before being replaced. This rule was introduced to speed up the game and cut down on constant pitcher changes, a problem that had stretched games to over 3 hours and 8 minutes on average in 2018. Here’s how it works and why it changed baseball.
What Exactly Is the Rule?
A relief pitcher must face at least three batters before being removed from the game, with two clear exceptions: if he gets injured or completes an inning. This prevents managers from making strategic substitutions after every batter, as they could before. The rule applies across MLB and Minor League Baseball.
Impact on Game Length
Pitcher changes were one of the main culprits behind longer games. With this rule in place, game duration dropped meaningfully. In 2019 (before the rule), games averaged 3 hours and 5 minutes; by 2021 that fell to 3 hours and 10 minutes, and the trend has continued toward faster-paced contests, though other factors like pitch tempo also played a role.
Bullpen Strategy Overhaul
Managers had to completely rethink how they deploy relief pitchers. Previously, a specialist for high-pressure situations could enter for a single batter; now he must be ready to face three. This has pushed teams to develop more versatile relievers with greater stamina, rather than ultra-specific specialists. Deep bullpens became even more valuable.
Exceptions and Special Cases
There are situations where a reliever can exit without facing three batters: if injured, if he completes an inning (even facing just one or two batters), or if it’s the end of the game. Also, if a batter is removed due to injury, that substitution doesn’t count against the reliever. These exceptions preserve necessary flexibility without undermining the rule’s intent.
| Aspect | Before 2020 | After 2020 |
|---|---|---|
| Pitcher Changes Per Game (Avg.) | ~5.5 changes | ~4.8 changes |
| Average Game Length | 3h 5min (2019) | 3h 10min (2021) |
| Minimum Batters Per Reliever | 1 (no limit) | 3 (or complete inning) |
| Bullpen Specialists | Very common | Less frequent |
FAQ
What if a reliever is pitching well but has to face a dangerous hitter?
The manager must leave the pitcher in the game or make the change knowing the new reliever must face at least three batters. This is the rule’s intention: forcing more deliberate, less reactive decisions.
Does the rule apply in both MLB and Minor Leagues?
Yes, since 2020 it applies across MLB, Minor League Baseball, and most international leagues including the Mexican League and Caribbean Series.
Can a reliever complete an inning while facing fewer than three batters?
Yes, if he completes the inning (three outs), he can be removed even if he faced fewer than three batters. This happens with stolen base outs, double plays, or defensive errors.
