Fantasy baseball Stat Focus: Alex Rios and the vagaries of BABIP

Alex Rios' low BABIP during 2011 hinted that he would rebound from that lackluster season.

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In 2011 Alex Rios had a disastrous season, hitting .227/.265/.348 with just 13 homers, causing many fantasy owners to stay as far away from him as possible the following season. Even though Rios had a strong 2010, owners took one look at the dreadful numbers in his age-30 season and decided it was the beginning of the end for Rios. While I didn't write him off immediately, I can't really blame people who did. And though I was open to grabbing Rios for my 2012 roster, I ended up with exactly zero shares of him.

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If only we'd dug a little deeper into Rios' statistics. There was plenty of evidence that supported the notion that 2011 was an anomaly, most strongly in one acronym that has swept the sabermetric community: BABIP.

BABIP stands for batting average on balls in play. By "in play," we mean balls that are in fair territory and remain in the ballpark. We can calculate BABIP with the following formula: Hits - Home Runs / At-Bats - Strikeouts - Home Runs + Sacrifice Flies. On average, a ball in play will go for a hit 30 percent of the time; therefore, the average major leaguer has a BABIP between .290 and .310. While speedy hitters can reliably post BABIPs higher than their batting average, we should view any outliers with skepticism, and can comfortably predict that a player will eventually regress to his career average BABIP.

All a hitter can control is how hard he hits the ball and, with varying degrees of skill, whether he pulls the ball or hits it the opposite way. After that, whether or not the ball falls in for a hit depends on a number of factors. Remember, both Brendan Ryan and Jhonny Peralta are starting shortstops in the majors right now. There are balls hit in the hole that no one but Ryan can get to, and there are balls in the hole that I can get to that would elude Peralta. Additionally, sometimes a batter crushes a ball right at someone. Other times, he bloops one into a perfect hole. Not all hits are created equal.

Now let's get back to Rios. Before his terrible 2011, he actually had a great year in 2010, hitting .284/.334/.457 with 21 homers and 34 steals. If we drill down to his batted-ball stats, we see a positive profile. He had a 16.9-percent line-drive rate, 45.1-percent ground-ball rate, 38-percent fly-ball rate and 11.5 home run/fly ball ratio. His BABIP in 2010 was a strong .306, right up toward the high end of the league average.

Fast forward to 2011, and we see a player with quite similar batted-ball stats; in fact, they were better in many respects. His line-drive rate was 18.4 percent. He decreased his ground-ball rate to 42.3 percent. His fly-ball rate remained essentially flat at 39.3 percent. His home run/fly ball ratio plummeted, however, to seven percent, resulting in more balls in play. In addition, he shaved 3.2 percentage points off his strikeout rate, thus increasing the pool of at-bats subject to BABIP. Still, with more line drives and fewer ground balls, it stands to reason that Rios' BABIP would hold steady, or perhaps dip just a bit thanks to having a larger share of balls in play.

So go ahead and guess what Rios' BABIP was in 2011. No peeking.

What did you say? .303? Maybe .300? Maybe you felt it dropped all the way to .290? No, no and no. Rios' BABIP in 2011 was a cool .237. Two-thirty-seven! Given what we know about BABIP, and considering we could see that Rios' skills didn't completely abandon him in 2011, it wasn't hard to predict a rebound 2012 season. Of course, we now know that Rios rebounded to the tune of .304/.334/.516 with 25 homers, 93 runs, 91 RBI and 23 steals. His BABIP? A robust .323, both more in line with his career numbers and league average, and exactly what we should have expected.

BABIP isn't a silly acronym or convoluted stat or something we just throw out there to fill space. It's easily definable, and it's worthwhile when projecting future performance. Being BABIP conversant should be a bow in every fantasy owner's quiver.