In baseball, the double switch is a type of player substitution. The double switch allows a manager to make a pitching substitution and defensive (fielding) substitution while at the same time improving the offensive (batting) lineup of a team. Specifically, the double switch is usually used to avoid a plate appearance (turn to bat) by a newly introduced pitcher (pitchers, especially relievers, are generally poor hitters).
A double switch consists of two substitutions made simultaneously. In the usual scenario: 1) a pitcher replaces a position player who will not be at bat soon, and 2) a position player replaces the former pitcher. The reason for this tactic is that a player must bat in the same spot in the batting lineup as the player he replaces. The advantage is that in the short-term the lineup is strengthened because a poor-hitting pitcher will not soon make a plate appearance. The disadvantage is that a position player (often referred to as the victim of a double switch) must be removed from play and replaced by another, often inferior, position player.
The advantage of the double switch over pinch hitting is that it uses up fewer players. If a relief pitcher is brought in before the at-bat, then the manager could substitute a pinch-hitter for him. However, this would require a new pitcher for the next half-inning. By pulling the double switch, a new pitcher brought in before the at-bat drops far enough in the lineup that he can be left in the game to pitch multiple innings before his spot in the lineup comes up.
Even though a position player was put in the game in place of the pitcher, and a pitcher was put into the game in place of a position player, the position player is not required to pitch, and the pitcher is not required to play the field. In baseball, a new player entering the game can play any defensive position (including pitcher) as long as he bats in the spot in the batting order in which the player he replaced was batting.
While the double switch plays an important role in the National League, the designated hitter (DH) rule in the American League has effectively eliminated the advantages of the double switch and is rarely used. The designated hitter's role is to bat in the pitcher's spot in the lineup. Major League rules do not allow a multiple substitution involving a DH to alter the lineup position of the DH. However, although uncommon, it is possible to forgo the DH privilege, e.g. if the DH becomes a position player, and then utilize the double switch later with that player. It can also be used by an AL team playing on the road during interleague play, because MLB rules call for the rules of the home team to be used (whether or not there is a DH) when teams from different leagues meet.
As a result, in the top of the eighth inning catcher Jason Varitek led off, followed by short-stop Julio Lugo, then Crisp. This gave the Red Sox an offensive advantage by not having to use a pitcher as the third batter in the inning, especially since pitchers in the American League rarely, if ever, bat during the regular season because of the designated hitter rule. The newly inserted pitcher would not have to bat until the ninth position in Francona's revised lineup. Varitek grounded out when he came to bat and Lugo walked. Crisp, batting third in the inning in place of the pitcher’s hitting position, ended up hitting a single to center field and eventually scored as part of a three-run inning that extended the Red Sox lead in Game Three to 9-5 at the end of 8 1/2 innings. Francona’s use of the double switch rule played a significant role in the 10-5 Red Sox victory and gave the American League champions a commanding three-games-to-none lead in the 2007 World Series.
Although this example shows an example of a double switch, it does not show the advantage to double switch in a game. This is because Manny Delcarmen was brought into the game in the next half inning replacing Timlin after only one inning pitched. So bringing in Timlin to pitch, and then simply pinch hitting for him in the next inning would have accomplished the same goal while leaving your starting 8 position players in the game.
|Before switch||After Switch||Batting position|
|CF Jacoby Ellsbury||RF Jacoby Ellsbury||4th|
|2B Dustin Pedroia||2B Dustin Pedroia||5th|
|1B Kevin Youkilis||1B Kevin Youkilis||6th|
|LF Manny Ramírez||LF Manny Ramírez||7th|
|3B Mike Lowell||3B Mike Lowell||8th|
|RF J.D. Drew||P Hideki Okajima||9th|
|C Jason Varitek||C Jason Varitek||Bats 1st next inning|
|SS Julio Lugo||SS Julio Lugo||Bats 2nd next inning|
|P Mike Timlin||CF Coco Crisp||Bats 3rd next inning|