The defensive shift– repositioning infielders from their conventional locations in response to a particular batter’s hitting tendencies– may be the most significant development in baseball defense since pitchers started actually trying to miss bats with their pitches. The basic idea is that defenses can take advantage of certain hitters who are known to possess extreme tendencies in terms of batted ball direction by loading up their infield defense in line with that batter’s tendencies.

David Ortiz is a decent example of a batter with a definite tendency to hit the ball in a particular direction. Here is a spray chart showing where he hit every ball during the 2012-2014 seasons:

Ortiz is a top-tier power hitter, so it isn’t surprising that he’s peppered the entire field. Focusing on his ground balls, though, reveals a pretty strong tendency to hit grounders to the right side of the infield. Opposing teams noticed and began to counter Ortiz defensively by shifting against him.

Probably the most common way to arrange a defensive shift is to move the second baseman into shallow right field, move the shortstop to the first-base side of second base, and shade the third baseman heavily toward second base. Teams also employ less and more extreme variations of this basic shift. Because a fielder needs to remain close to first base, teams almost exclusively shift to overload the right side of the infield. This, in turn, means that teams almost always shift, if at all, against left-handed hitters, who, as a population, generally hit the ball to the right. Ortiz is a lefty, and his spray chart evidences the expected pattern.

No player faced a full defensive shift more than Ortiz in 2015, when opposing defenses shifted on more than sixty-three-percent of his plate appearances. The most effective antidote for the shift is a bunt to the exposed third-base side, but Ortiz, now at forty years old and at least 6’3″ and 230 pounds, has not been the bunting sort of late or, really, ever. He’s a big, left-handed power hitter in the last year of his career, and, as concerns the defensive shift, he’s just going to have to take his lumps.

A little further down that list of 2015’s most-shifted appears Victor Martinez in the #22 spot. Martinez spent much of 2015 injured, so he only made 485 plate appearances, seeing a full shift on roughly forty-three percent of them. Like Ortiz, Martinez is heavier, slow, and hits from the left side, and his 2012-2014 spray chart shows similar batted-ball tendencies to Ortiz’s:

One way in which Martinez is unlike Ortiz, though, is that, while both bat left-handed, Martinez also bats right-handed. Continue reading →