Batting order (baseball)

In baseball, the batting order or batting lineup is the sequence in which the members of the offense take their turns in batting against the pitcher. The batting order is the main component of a team's offensive strategy. In Major League Baseball, the batting order is set by the manager, who before the game begins must present the home plate umpire with two copies of his team's lineup card, a card on which a team's starting batting order is recorded. The home plate umpire keeps one copy of the lineup card of each team, and gives the second copy to the opposing manager. Once the home plate umpire gives the lineup cards to the opposing managers, the batting lineup is final and a manager can only make changes under the Official Baseball Rules governing substitutions. If a team bats out of order, it is a violation of baseball's rules and subject to penalty.

According to The Dickson Baseball Dictionary, a team has "batted around" when each of the nine batters in the team's lineup has made a plate appearance, and the first batter is coming up again during a single inning.Dictionary.com, however, defines "bat around" as "to have every player in the lineup take a turn at bat during a single inning." It is not an official statistic. Opinions differ as to whether nine batters must get an at-bat, or if the opening batter must bat again for "batting around" to have occurred.

In modern American baseball, some batting positions have nicknames: "leadoff" for first, "cleanup" for fourth, and "last" for ninth. Others are known by the ordinal numbers or the term #-hole (3rd place hitter would be 3-hole). In similar fashion, the third, fourth, and fifth batters are often collectively referred to as the "heart" or "meat" of the batting order, while the seventh, eighth, and ninth batters are called the "bottom of the lineup," a designation generally referring both to their hitting position and to their typical lack of offensive prowess.

At the start of each inning, the batting order resumes where it left off in the previous inning, rather than resetting to start with the #1 hitter again. While this ensures that the players all bat roughly the same number of times, the game will almost always end before the last cycle is complete, so that the #1 hitter (for example) almost always has one plate appearance more than the #9 hitter, which is a significant enough difference to affect tactical decisions.

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