A defensive substitution in the game of baseball

Baseball

Baseball is a bat-and-ball sport played between two teams of nine players each. The aim is to score runs by hitting a thrown ball with a bat and touching a series of four bases arranged at the corners of a ninety-foot diamond...

 occurs when a currently non-playing player is placed into the field in place of a starting player, typically due either to injury or the appearance of a pinch hitter

Pinch hitter

In baseball, a pinch hitter is a substitute batter. Batters can be substituted at any time while the ball is dead ; the manager may use any player that has not yet entered the game as a substitute...

. In the American League

American League

The American League of Professional Baseball Clubs, or simply the American League , is one of two leagues that make up Major League Baseball in the United States and Canada. It developed from the Western League, a minor league based in the Great Lakes states, which eventually aspired to major...

, a pinch hitter is usually substituted for the position player in whose place he batted (although another common substitution is pinch-hitting a utility infielder

Utility infielder

A utility infielder is a baseball player, usually one who does not have a regular starting role on the team and who is capable of playing more than one of the four defensive infield positions: second base, third base, shortstop, and less typically first base...

 for a second baseman and subsequently switching him for the shortstop

Shortstop

Shortstop, abbreviated SS, is the baseball fielding position between second and third base. Shortstop is often regarded as the most dynamic defensive position in baseball, because there are more right-handed hitters in baseball than left-handed hitters, and most hitters have a tendency to pull the...

 in the field while moving the shortstop over to the now-vacant second base position). In the National League

National League

The National League of Professional Baseball Clubs, known simply as the National League , is the older of two leagues constituting Major League Baseball, and the world's oldest extant professional team sports league. Founded on February 2, 1876, to replace the National Association of Professional...

, which does not use the designated hitter

Designated hitter

In baseball, the designated hitter rule is the common name for Major League Baseball Rule 6.10, an official position adopted by the American League in 1973 that allows teams to designate a player, known as the designated hitter , to bat in place of the pitcher each time he would otherwise come to...

 rule, pinch hitters sometimes bat for pitcher

Pitcher

In baseball, the pitcher is the player who throwsthe baseball from the pitcher's mound toward the catcher to begin each play, with the goal of retiring a batter, who attempts to either make contact with the pitched ball or draw a walk. In the numbering system used to record defensive plays, the...

s. However, another common pitcher-substitution strategy in the NL is the double switch, in which a pitching change is coupled with a pinch-hitter who is also defensively substituted for a second player.