Infield shift

The infield shift is a generic term used in baseball to describe an extreme defensive realignment from the standard positions to blanket one side of the field or another. Used almost exclusively against left-handed batters, it is designed to protect against extra base hits pulled hard into the gaps between the fielders on the right side.

Originally called the "Boudreau" or "Williams" shift, the strategy is often associated with Ted Williams, but it was actually first employed against Cy Williams during the 1920s. It was later used against Ted Williams during the 1946 World Series between the Red Sox and the Cardinals as a defensive gimmick by St. Louis manager Eddie Dyer to psych out and hopefully contain Boston slugger Williams. It was devised by Cleveland Indians manager Lou Boudreau on a blackboard between games of a doubleheader in July 1946 to halt Williams' hot hitting. "I always considered The Boudreau Shift a psychological, rather than a tactical victory," wrote Lou Boudreau in his book, Player-Manager. The shift has been employed since then to thwart extreme pull hitters (mostly lefties), such as Barry Bonds, Ryan Howard, Jason Giambi, David Ortiz, and Mark Teixeira.

Typically the third baseman moves to the left where the shortstop plays; the shortstop plays to the right of second; the second baseman plays between first and second and usually on the right field grass; the center fielder plays right-center; and the first baseman and right fielder hug the foul line. Sometimes, the third baseman will move to where the shortstop moves, since the fielder on the left side plays shortstop, it makes sense to have the actual shortstop there. While this is the most common type of defensive shift seen in baseball, there are numerous variations that can be implemented according to the hitting ability of the batter. For example, an effective defensive shift against Joe Mauer would have the infield shifted for a pull-happy left hander, and the outfield shifted for a pull-happy right-hander, due to Mauer's uncommon tendency to pull nearly all of his groundballs, and hit nearly all of his flyballs to the opposite field.

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