Win–loss record (pitching)

In baseball and softball, a pitcher's win–loss record (also referred to simply as their record) indicates the number of wins (denoted "W") and losses (denoted "L") they have been credited with. For example, a 20–10 win–loss record would represent 20 wins and 10 losses.

In each game, one pitcher on the winning team is awarded a win (the "winning pitcher") and one pitcher on the losing team is given a loss (the "losing pitcher") in their respective statistics. These pitchers are collectively known as the pitchers of record. The designation of win or loss for a pitcher is known as a decision, and only one pitcher for each team receives a decision. A starting pitcher who does not receive credit for a win or loss is said to have no decision. In certain situations, another pitcher on the winning team who pitched in relief of the winning pitcher can be credited with a save, and holds can be awarded to relief pitchers on both sides, but these are never awarded to the same pitcher who is awarded the win.

The decisions are awarded by the official scorer of the game in accordance with the league's rules. The official scorer does not assign a winning or losing pitcher in some games which are forfeited, such as those that are tied at the time of forfeiture. If the game is tied (a rare event), no pitcher is awarded any decision. A pitcher's winning percentage is calculated by dividing the number of wins by the number of decisions (wins plus losses), and it is commonly expressed with three decimal places.

In Major League Baseball, the winning pitcher is defined as the pitcher who last pitched prior to the half-inning when the winning team took the lead for the last time.

There are two exceptions to this rule. The first is that a starting pitcher must complete five innings to earn a win (four innings for a game that lasts five innings on defense). If he fails to do so, he is ineligible to be the winning pitcher even if he last pitched prior to the half-inning when his team took the lead for the last time, and the official scorer awards the win to the relief pitcher who, in the official scorer's judgment, was the most effective.

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