About a decade ago, teams began to ignore more than a century of "That's The Way It’s Always Been Done" defensive doctrine and instead focus on an elementary idea: What is the most advantageous placement of our seven position players?
The initial success of the Tampa Bay Rays and other teams in shifting defenders around the infield is now universally copied. What seemed like mad-scientist stuff back then now seems entirely routine.
It’s possible that the extra layer of analysis could soon extend into the outfield with some teams. Some evaluators have mulled the concept of using a four-man outfield under certain circumstances as a way of reducing the odds of big damage. More and more hitters and coaches have focused on developing swing mechanics of getting the ball in the air, and the addition of one more fielder to the outfield might be increasingly considered.
"The more that I think about it," one evaluator said, "the more that I think it can make sense."
Adding a fourth outfielder in certain situations could be the next advantage teams seek. Juan DeLeon/Icon Sportswire
First and foremost -- and quite obviously -- the hitter would have to have demonstrated a tendency to generate fly balls to his pull side. Think about someone such as Greg Bird of the New York Yankees, whose rate of ground balls to fly balls was 0.52 in 2015, the highest of any player with at least 170 plate appearances that season. Or maybe the Minnesota Twins' Brian Dozier, who hits the ball in the air a lot and has the highest rate of pulling the ball the past two seasons.
The pitcher would have to be someone who might be more apt to induce fly balls. Probably never someone such as Marcus Stroman, who led the majors in ground ball percentage last year (60.1 percent), but more like Marco Estrada, who had the third-highest fly ball rate, at 48.2 percent.
The game situation would have to be right: mostly with two outs, some evaluators mentioned, when the odds of an extended rally are greatly diminished. If a slow, lumbering slugger opted to cut down on his swing to single through an open infield, rather than swing big, that could be a plus for the defense.
One possible example: If the right-handed hitting Dozier came to the plate with two outs, a team could shift an infielder to the outfield, perhaps with the left fielder playing closer to the foul line, the center moved to deep left-center, the right fielder now moved to center, and the infielder -- theoretically the least adept of the four in the outfield -- in right field, where Dozier is least likely to hit the ball.
You’d have to have the right personnel to make it more palatable for the defense, as one evaluator noted. The Chicago Cubs have great options to add a fourth outfielder from play to play because of the experience of Ben Zobrist and Kris Bryant in the infield and outfield. On the other hand, the Twins might see less benefit in shifting Miguel Sano out of the infield in specific situations.
Placing the fielders in the spots where they most likely could catch the ball would be a priority, but the shift to four in the outfield could pressure hitters out of an emotional comfort zone. The Cubs' Joe Maddon has given voice to this, noting that every time you put in front of a hitter something he hasn't seen before, you can get into his head -- and that can serve the interests of the pitcher even before he throws a pitch.
A four-man outfield might also compel a slugger such as Bird or Dozier to make a choice. The hitter can alter his swing in an attempt to take advantage of the enormous spaces that would open up in a three-man infield, but in doing so, he would sacrifice the opportunity to do what hitters are increasingly focused on: driving the ball into the air for big damage.
"If you get a slugger to try to slap a single through the infield, he’s probably doing you a favor," one evaluator said. "Would you want David Ortiz trying to hit a single in the ninth inning against you rather than trying to hit a homer? Of course."
Late in close games, teams will often position their corner infielders on the lines and back up their outfielders closer to the fences in what is commonly known as a no-doubles defense. The use of a four-man outfield -- against boppers who mostly hit fly balls -- could be a similar weapon, especially with two outs.
When Maddon managed the Rays, he used a four-man outfield against Ortiz and Jim Thome. The concept has mostly been dormant since then, but it's possible that it'll be revitalized at a ballpark near you.