For more than a century, the defensive positioning of baseball players seemed as standard as the game's white balls, wooden bats and chalked foul lines.
But turn on a Yankees game these days and you're bound to see an alignment that has the shortstop playing a few steps closer to third base, the third baseman on the grass behind or to the right of second base and the second baseman camped out somewhere in shallow rightfield.
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And then they'll rearrange themselves for the next hitter.
Changing alignments have been commonly referred to as an "infield shift,'' but really, it has morphed into something much bigger. What's happening this season with the Yankees, and throughout baseball, is a complete reboot of infielders' positioning depending on each hitter's tendencies.
Armed with data on nearly every hitter in the major leagues -- information that indicates where he is most likely to hit grounders and line drives -- the Yankees have made it a priority this season to position their infielders in those very spots on the field.
"The thing about the shifting is you're playing the percentages,'' manager Joe Girardi said, "and for the most part, you're going to be right.''
This season the Yankees have employed an infield shift on 531 balls that have been put in play (through Thursday's games), according to Baseball Info Solutions, a statistical analysis company that tracks infield positioning. That's about 5.8 times per game. The Yankees' total -- which ranks second only to the Astros (806) -- puts them on pace to more than double their 2013 total of 475 shifts on balls in play.
The Yankees' shift strategy was developed by the team's quantitative analysis department during the offseason, and according to assistant general manager Billy Eppler, coaches and players have bought in.
"For 100 years, defenses just arbitrarily played in positions not based on where hitters were hitting the ball,'' first baseman Mark Teixeira said. "So in a way it's natural to have this kind of progression.''
Added third baseman Kelly Johnson: "I'm surprised it took this long, really. You would have thought someone would have eventually said this guy keeps hitting the ball in the same exact spot. Why don't we just put a guy over there?''
The Williams shift
The infield shift can be traced to 1946, when Indians player-manager Lou Boudreau employed it against Red Sox slugger Ted Williams in the second game of a doubleheader after Williams had gone 4-for-5 with three home runs.
But even though it's been around the game for decades, it wasn't a common occurrence. The infield shift started to gain steam a decade ago as a strategy to defend against lefthanded sluggers who liked to pull the ball such as Barry Bonds, David Ortiz, Ryan Howard, Adam Dunn and Teixeira. Teams started moving the shortstop to the first-base side of second base and, in turn, moved the second baseman into shallow rightfield, turning hits through the hole into outs.
Teixeira said that in 2011, he grew so frustrated about hitting the ball right at the extra fielder on the right side that he changed his mindset going into the next season. He vowed to take advantage of the empty left side, either by dumping singles into the outfield or -- gasp -- bunting.
That was a mistake.
Teixeira got off to a slow start, went back to pulling the ball and finished with then-career lows of 24 home runs and a .475 slugging percentage in an injury-shortened season.
It took away hits -- and maybe got in his head, too.
"That's part of the goal here,'' Twins manager Ron Gardenhire said. "You get them out of their normal thought process of just getting a good pitch to hit and rip it. I think when you start seeing guys trying to beat the shift, then you've probably started something good.''
Inside the numbers
As more teams began using the infield shift, the folks at Baseball Info Solutions took notice and started keeping tabs of the instances -- both for their own use and to sell the info to teams.
Created in 2002, the company says its goal is to "specialize in collecting, interpreting and disseminating baseball statistics.'' Based in Coplay, Pennsylvania, Baseball Info Solutions sells its statistical data and analysis to major league clubs.
"We started doing defensive positioning-focused products about 10 years ago, and as you might expect with all the shift interest in baseball the last couple of years, that's really exploded the last two years or so,'' said Ben Jedlovec, vice president for product development and sales.
A statistics and sport management major at Rice University, Jedlovec said his company is contracted to work with nearly 20 clubs (he declined to name them). Every game is watched by three of the firm's people, using the various television broadcasts and camera angles available. For every ball in play, they record where the fielder set up, where the ball was hit and whether it was a grounder, soft line drive, hard line drive or otherwise.
The company began tracking the shifts on balls in play in 2010, and the increase since then has been stark. There were a total of 2,357 shifts in 2011, 4,577 in 2012 and 8,134 in 2013. This year they say the league is on pace for more than 14,000 shifts.
The Yankees' trend is similar.
According to Baseball Info Solutions, the Yankees shifted on balls in play 74 times in 2011, 136 in 2012 and 475 times in 2013. This year they're on a pace to use more shifts than the previous three seasons combined -- and they'll likely beat that figure by August.
But not every team is as shift-happy. The Mets, for example, are not quite ready to join the masses. "Our general organizational philosophy is we believe in the shift, but we want to be cautious,'' assistant general manager John Ricco said. "Because a lot of times you're dealing with a smaller sample size.''
The Mets have used the shift on 148 balls in play (through Thursday), placing them 21st in the majors. Last year the Mets were 19th with 177 shifts on balls in play.
More often than not, the Mets use the shift only against lefthanded-hitting sluggers who like to pull the ball such as Howard. Those are the players with the undisputed track records of hitting the ball to a certain spot. "Occasionally we'll do it to a less obvious player,'' Ricco said, "but it's not going to be to the extent of these other teams.''
Determining how successful an infield shift is can be tricky, Jedlovec said. Still, his firm keeps a stat called "Shift Runs Saved,'' which he said is calculated "by comparing how frequently plays are made in the shift compared to similar balls in play in traditional alignments.''
The Yankees, for the first three months for example, were minus-10 runs saved without the shift, meaning that when they were in normal alignment, they allowed 10 runs more than an average defense would have with the balls hit to the same spot.
With the shift in place, that figure improves by three runs to minus-7.
"For a team like the Yankees, putting their infielders in the right spots on the field is even more vital because their fielders don't have the range to compensate for suboptimal positioning,'' Jedlovec said.
Neither the Yankees nor Mets would say what stats they keep to measure the shift's success.
Plenty of times balls have been hit to where the fielders would have been in a normal alignment, but the Yankees discount those, trusting that an opposing hitter's spray chart won't lie over the long term.
"It's human nature that you're going to remember the one you got beat by it a little bit more than the one you saved because of it,'' Eppler said.
And that the Yankees continue to use the overshift illustrates how important they think it is. In other words, it's not going anywhere.
"I think for the most part, we're definitely on positive in the balls we've gotten to,'' Girardi said. "Every once in a while, you're going to run into someone who accidentally goes the other way or check swings. Those sort of things are going to happen.
"I think it's been positive for our club. I'm in favor of it.''
Before every series, Yankees coaches discuss the latest statistical data and trends handed down from the front office to defensive strategy for each hitter. The plan is relayed to the fielders during their pre-series scouting meeting and often can be changed on the fly, batter to batter, depending on the count.
Watch infield coordinator Mick Kelleher during a game. He stands on the top step of the Yankees' dugout. After each batter, the infielders will look to him for a sign that tells them where to go.
Against a lefthanded hitter, the third baseman sometimes will run across the diamond and play alongside second baseman Brian Roberts. Other times, if the shift is less drastic, shortstop Derek Jeter will move a few steps behind second base and the third baseman will have to cover more ground.
"There are a lot of subtleties to the shift now,'' Jedlovec said. "It's more than just is the shift on or is it off? It's optimizing defensive positioning even outside of the shift.''
This year the Yankees also have shifted against righthanded hitters. Teams often frowned upon that because of the hole it creates on the right side with the first baseman having to stay reasonably close to the bag to take throws on grounders.
The Yankees' outfield positioning is not impacted by where they place their infielders, coaches say, because they view it as two separate defensive alignments.
"We're going to sit here a decade from now,'' Eppler said, "and I think it's going to be second nature.''
Most baseball insiders agree that the next stage in the evolution of the shift is whether hitters decide to adjust their hitting styles to the defenses they face.
It's a delicate balance, as the act of hitting can be complicated in itself. It's not just having the ability to hit a 96-mph fastball; it's being ready to adjust when you think a fastball is coming and a 75-mph curveball or an 82-mph changeup is thrown instead. Should hitters concern themselves where the infielders are lining up, too?
Most successful hitters say it's not worth their time to try to change anything.
"For me they're just moving the second baseman over by the bag,'' said Oakland's Josh Donaldson, a righthanded hitter who rarely sees defenses like that. "And if that's what they want to do, then that's what they're going to do. I'm not going to say a whole lot.''
Still, a hitter can't help but notice where the defenders are, especially if they're out of their usual positions.
"You start to put pressure on hitters to do something different,'' Johnson said.
Teixeira's struggles from a few years ago represent proof of what happens when the shift gets inside a hitter's head. That frustrating experience has helped his mindset evolve.
Nowadays, Teixeira still faces these funky-looking defensive alignments nearly every time he steps to the plate, at least when he's hitting lefthanded, but he says he's moved beyond thinking about it.
"I don't change anything,'' Teixeira said. "I'm not trying to hit ground balls, righthanded or lefthanded, so I just try to do the same thing -- drive the ball in the alley.''
Jeter is one player who would welcome the challenge of facing a shift. "They don't shift me. I wish they would shift me,'' he said. "I don't care where they shifted, which direction they shifted, but I wish they would. You know how easy it would be to get hits if somebody played a shift? The whole infield on one side? I'm just talking about for me . . . I should be able to make an adjustment to that. I can only speak for myself.
"Write that: I wish they'd play a shift on me.''
With Erik Boland