Josh Satin throws during spring training practice on Saturday, Feb....

Josh Satin throws during spring training practice on Saturday, Feb. 22, 2014, in Port St. Lucie, Fla. Credit: Newsday / Alejandra Villa

Hall of Famer Wee Willie Keeler is known for two things: not being very tall and for allegedly saying his batting strategy was to "hit 'em where they ain't."

Keeler (5-feet-41/2) played from 1892-1910. Advanced stats in those days consisted of counting balls, strikes and the length of waxed handlebar mustaches.

But is hitting balls where "they" -- fielders -- "ain't" truly a skill that can be mastered? In this day and age, where everything in baseball is counted and analyzed, there is an advanced stat that attempts to answer that question.

The stat is BABIP, which stands for Batting Average on Balls in Play.

BABIP is exactly what it seems: A number that tells you how many hits a batter gets on balls in the field of play (or, in the pitching version, how many a pitcher gives up). Generally, 30 percent of balls in play fall in, so a league-average BABIP is .300.

The basic formula is:

BABIP = (H - HR) / (AB - K - HR + SF + SH).

According to Baseball Prospectus, BABIP for hitters is "a skill, based on how well they are able to hit and place the ball, along with their [foot] speed."

That brings us to Mets corner infielder Josh Satin. He is something of a BABIP wizard, and not because of his (negligible) foot speed.

Satin is not going to beat out a lot of bunts or infield rollers, two things that help increase BABIP. But perhaps because of skill or perhaps because of coincidence, Satin has had a high BABIP in his two small samples of major-league play.

And he is aware of it.

"I know what it stands for," Satin said this past week. "I know what it is. I know that I always have a high one."

In 2011 with the Mets, Satin hit .200 in 27 plate appearances. But his BABIP was .357.

In 2013, Satin got much more of a chance with the Mets. In 221 plate appearances, he hit .279 with a .376 on-base percentage and a .405 slugging percentage.

His BABIP was .379, which would have put him among the major-league leaders if he had enough plate appearances. The highest BABIP last season among regulars was .394, by Chris Johnson of the Braves.

A high BABIP in one year could mean the player has just been luckier than usual and will lose some of those hits in the following season as "the breaks" even out. Conversely, a low BABIP could mean the player is due to improve as his luck improves. A consistent BABIP over seasons could be a skill.

Satin, 29, is a righthanded hitter with a keen batting eye (but without power) who should be part of a first base platoon at Citi Field this season. If Satin keeps his BABIP high, he'll likely keep his big-league job. A regression below the league average could mean he'll be enjoying most of the summer at Triple-A Las Vegas.

Predicting whether a player is going to improve or regress is why front-office types get paid handsomely. BABIP can be a useful tool when it comes to predicting which players are going to be more (or less) valuable from year to year, although it is generally accepted to be more reliable in predicting the fluctuating stats of pitchers than hitters.

So why is Satin a high BABIP guy? He has a theory.

"My whole philosophy of hitting -- which is kind of similar to what [the Mets] want -- is swing at the best pitch you're going to get and don't swing at marginal pitches, which I think creates maybe a few more strikeouts but allows you to square the ball up more," Satin said. "You square the ball up more, you're going to have a higher batting average on balls in play, especially if you strike out a little more. It's not like it's a surprise to me that I have a high ."

That's not to say Satin is a BABIP believer. Just because you understand something doesn't mean you agree with it.

"Do I think that having a high batting average on -- whatever the thing is -- is lucky? Sometimes," Satin said. "But if you put enough balls in play hard, it's going to work out.''

Hit 'em where they ain't? Maybe it just has to be updated to "hit 'em hard where they ain't." Hopefully, Wee Willie wouldn't object.