What a Perfect Game Means in Baseball Explainer
A perfect game is one of baseball’s rarest pitching achievements. In a regulation game, one pitcher or a combination of pitchers retires every opposing batter without allowing anyone to reach base safely. In a standard nine-inning game, that means 27 batters faced and 27 outs recorded.
No hits, walks, hit batters, or fielding errors can put a runner on base. A dropped third strike, catcher’s interference, or any other event that allows a batter or runner to reach safely also ends perfection. An error that does not result in a runner reaching may not, by itself, break the perfect game.
A no-hitter is broader. It prohibits hits but can include walks, errors, hit batters, or other baserunners. Every perfect game is a no-hitter, but most no-hitters are not perfect. The official scoring decision on a borderline hit or error can therefore affect whether a no-hitter survives, while perfection also depends on every plate appearance ending in an out.
If the score remains tied after nine innings, perfection must continue through extra innings until the game is completed under the applicable rules. Modern special rules can complicate how inherited or automatic runners are treated, so official recognition follows the league’s definitions. The essential idea remains simple: the defense gives the opponent no successful trip to first base.
Every batter faced must be retired and no opponent may reach base safely. A normal nine-inning perfect game contains 27 consecutive outs.
The achievement can be completed by one pitcher or, where recognized, by multiple pitchers sharing the game.
A no-hitter allows baserunners through walks, errors, hit batters, and other non-hit events. A perfect game allows none.
That makes perfection a narrower category: all perfect games are no-hitters, but a no-hitter can be far from perfect.
Official scorers distinguish hits from errors, which can preserve or end a no-hitter. Perfection focuses on whether anyone reached safely.
If the game extends beyond regulation, the streak of retired batters must continue through the completed game under league rules.
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