MILWAUKEE -- You could see it in the way he arched his back in agony. For a moment, Jimmy Nelson had forgotten he pitched for the National League's "shiftiest" team.
Nelson was fighting hard for outs against the Twins at Miller Park on Wednesday. For a second straight inning, Minnesota put a pair of runners aboard with two outs. Up to the plate stepped Eduardo Nunez, a right-handed hitter not known for power, yet who drew an extreme infield shift. Second baseman Scooter Gennett played on the shortstop side of the bag.
Nelson precisely executed the curveball he wanted, inducing just the bouncing ball he wanted. But the right side of the infield was vacant, and Nunez had a run-scoring single.
"It does take some getting used to," the 26-year-old right-hander said. "It used to be the pull-power guys. Now it seems like it's every hitter.
"You just have to be more aware of it and understand the alignment. It means being more aware of your surroundings. It's a lot more intense."
And yes, Nelson conceded, it sometimes drives a pitcher crazy.
"We'll probably lose a game this year because a guy beats the shift," Brewers manager Craig Counsell said. "It's going to happen. Like all this stuff, it's not the answer. It's a way we choose to try to be just a little bit better and catch more ground balls over the course of a season."
The first thing you need to know about the Brewers' increased employment of infield shifts is that the minds behind them prefer not to use that term.
"Shift" implies the infielders moving in unison, but what the Brewers and other teams are doing can be more complicated, depending on the hitter and the situation. For a left-handed hitter who pulls the ball on the ground, for example, the third baseman sometimes leaves his post entirely and plays between the shortstop and the second baseman.
"Optimal positioning" is general manager David Stearns' preferred term.
Stearns came to the Brewers from the front office of the Astros, one of the clubs driving the dramatic changes in infield alignments. Shifts are up as much as 70 percent in Major League Baseball, according to recent data from Baseball Info Solutions, a pre-eminent tracker of the trend, with teams like the Brewers, Rockies, Angels and Yankees close behind the Astros leading the way.
Tracking shifts is tricky, because the publicly available data only accounts for balls in play, and ignores walks and strikeouts. The data available at FanGraphs.com through Sunday's games says the Astros have led MLB in shifts, using some degree of creative infield positioning for 296 batters who produced balls in play. The Brewers were second with shifts on 247 batters, followed by the Rockies (224) and Angels (220).
The least shifty teams in the NL were the Marlins and Mets, at 71 batters apiece. The Red Sox employed the fewest shifts in baseball, moving the infielders for only 56 batters.
The Brewers shift because they believe it creates outs. The team's coaches received an email from the front office on Saturday morning that said shifts had produced a net gain of 10 outs through Milwaukee's first 17 games.
Now that figure is somewhat malleable, since it involves much subjective judgement. Besides the obvious hits and outs attributed to the shift, there are many other balls in play best described as "would've, could've or should've," such as shifts that took away a hit but cost a double play because infielders were not positioned to make a turn. The Brewers analyze those plays and discuss possible solutions.
The obvious plays are the ones that stand out. There was the Nunez hit, which hurt. But there have also been positive outcomes, including Gennett's diving stop of a Cameron Rupp grounder up the middle in Friday's loss to the Phillies. It took away an RBI hit.
Gennett actually went to his left to make the play, just like a shortstop.
"They need to maybe change the title of my position," Gennett said with a smile. "It's definitely not a normal second base."
Under former bench coach Rich Dauer in the mid-2000s, the Brewers helped pioneer the current era of infield shifts. Back then, Dauer used his instincts to position fielders. Today, it's done with hard data.
Myriad factors go into the Brewers' positioning, starting with the team's own internal scouting reports and data from third-party vendors, which have sprung up in abundance in recent years. That material is distilled by the Brewers' advance scouting and research and development teams into a larger pre-series scouting report distributed to Counsell and his coaches. Carlos Subero, the team's infield instructor, watches hours of his own video and works with infielders before each game to get comfortable at the various spots on the field they'll see.
During games, Subero positions fielders with input from Counsell and bench coach Pat Murphy. From inning to inning, situation to situation, it's something of an art.
"It's not 'yes or no' on a shift," Counsell said. "It's all the dynamics that a game presents. It's challenging for the infielders, and they've done a nice job of it."
Hitters will determine how long this revolution lasts. As long as they're bunting for singles, teams are likely to continue. But if hitters, in time, are able to consistently drive the baseball against the shift, then defenses have a problem.
"There will be a breaking point," Stearns said. "It might take us a while to recognize it, but it will come. I don't think we're there yet."
Counsell believes the same.
"The game has an incredible way of balancing itself out when it recognizes you go too far," Counsell said. "That's what's so beautiful about it. The game won't let you get too drastic. That's what's great about it, and that's what's fun about it."
Adam McCalvy has covered the Brewers for MLB.com since 2001. Follow him on Twitter @AdamMcCalvy, like him on Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.