Plate appearance

In baseball statistics, a player is credited with a plate appearance (denoted by PA) each time he completes a turn batting. A player completes a turn batting when: he strikes out or is declared out before reaching first base; or he reaches first base safely or is awarded first base (by a base on balls, hit by pitch, or catcher's interference); or he hits a fair ball which causes a preceding runner to be put out for the third out before he himself is put out or reaches first base safely (see also left on base, fielder's choice, force play). In other words, a plate appearance ends when the batter is put out or becomes a runner. A very similar statistic, at bats, counts a subset of plate appearances that end under certain circumstances.

While at bats are used to calculate such important player hitting statistics as batting averages, slugging percentages and on-base percentages, plate appearances have no such statistical value. However, at season's end. a player must have accumulated 502 plate appearances during a season to be ranked in any of these categories. For example, suppose Player A, with 510 plate appearances and 400 at bats, gets 100 hits during the season and finishes with a .250 batting average. And suppose Player B, with 490 plate appearances and 400 at bats, gets 110 hits during the season and finishes the season with a .275 batting average. Player B, even though he had the same amount of at bats as Player A and even though his batting average is higher, will not be eligible for season-ending rankings because he did not accumulate the required 502 plate appearances, while Player A did and therefore will be eligible.

Rule 10.22(a) of the Official Baseball Rules make a single allowance to the minimum requirement of 502 plate appearances. If a player has less than that minimum amount, but if that player would win the batting, slugging or on-base percentage title if he had that minimum amount, then the amount of at bats he is short may be added to his at bat (and hence plate appearance) total so that he may win that title (assuming that his batting average, which would have to be recalculated after these extra at bats were added, would still be the best in his respective league.) For example, in 2012, Melky Cabrera, then of the San Francisco Giants, finished the season with a league-high .346 batting average, but he had only 501 plate appearances, one short of the required 502. Per the rule, an extra at bat should have been added to his total because, after it is added and his batting average recalculated, he still would have won the batting title. Melky's case, however, turned out differently. The reason Melky finished the season with only 501 at bats was because he was suspended in mid-August when he tested positive for illegal performance-enhancing drugs. Melky was still eligible for that extra plate appearance, but he requested that that extra plate appearance not be added to his total, and that he not be considered for the batting crown, because he admitted that his use of performance-enhancing drugs had given him an unfair advantage over other players. As a result, Melky's name is nowhere to be found on the list of 2012 National League batting leaders.

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