A procedure by which a team can request that the league correct some violation of the rules that occurred during a game. Teams may protest decisions by umpires that run contrary to the rules, and failures by the home team of its responsibility to maintain the ballpark in good order. Teams may not protest judgement calls or decisions by umpires, replay officials, or other league officials. Only situations where actions clearly contrary to the rules may be protested.
In Major League Baseball, when a protestable event occurs, the aggrieved team must immediately notify the umpires of the intent to protest the game, and the nature of the grievance. At that point, the official scorer must take care to record the exact state of the game at that moment. The umpires will notify the other team that the game is being played under protest. (If the protested event occurred on a game-ending play, the protesting team has until the following morning to file a protest with the league.) The league will review the situation and the eventual outcome of the game, and make a decision, usually the next day.
If the protesting team won the game, the protest will be disallowed regardless. Otherwise, if the league occurs that an action contrary to the rules did happen, it will impose any conditions that will nullify the improper action, and then usually ordered the game resumed from that point on a future day. (It is a similar situation to a suspended game.)
Protests being upheld is rare in Major League Baseball. Even if the league agrees that an improper action occurred, they will usually not uphold a protest if the league believes that the improper action did not materially effect the outcome of the game.
Two examples of MLB game protests that have been upheld (both from Retrosheet):
- August 25, 1948, Brooklyn Dodgers at Pittsburgh Pirates. Bottom of the 9th, 2 out. Brooklyn began the bottom half of the inning with an 11-6 lead, but the Pirates have already scored three runs in the inning, and have runners at first and third. With the pitcher due, the Pirates send up infielder Eddie Brockman to pinch-hit; the Dodgers respond by sending reliever Carl Erskine to the mound. But when the count reaches 3-1 to Brockman, the Dodgers remove Erskine and substitute pitcher Hank Behrman. This is clearly contrary to the rules at the time, which require a pitcher entering the game to complete pitching to at least one batter, but the umpires allow it. Against Behrman, Brockman grounds out to end the game for an apparent 11-9 Dodgers victory. However, the Pirates protest the game. The league agrees that the umpires allowed a rules violation to occur, and orders the game resumed with Erskine on the mound, pitching to Brockman with a 3-1 count. The game resumes on September 21. Erskine walks Brockman and then is replaced by Behrman, who surrenders a double to Stan Rojek that drives in all three baserunners, for a 12-11 Pirates victory.
- August 19, 2014, San Francisco Giants at Chicago Cubs. The Cubs, who lead the game 2-0 on a second-inning homer by Anthony Rizzo, have just finished putting out the Giants in the top of the 5th inning when a storm arrives. The grounds crew is unable to get the tarp over the infield, and the infield is soaked by heavy rain. After waiting four hours, the umpires call the game. Since the Cubs had the lead going into the inning, the game has gone far enough to be an official game, resulting in a Cubs victory. The Giants protest that the calling of the game was caused by the Cubs' failure to get the infield covered, rather than by the rain per se. Since the tarp is "equipment under control of the home club", the league agrees, and orders the game continued. It resumes on August 21, with the Cubs coming to bat in the bottom of the 5th. However, the protest ends up being for naught, as the Cubs go on to win anyway, 2-1.