“Do you know what the difference between hitting .250 and .300 is? That's 25 hits...25 hits in 500 at bats is 50 points...ok. There's 6 months in a season. That's about 25 weeks.That means if you get just one extra flare a week, just one. A gork, you get a ground ball, you get a ground ball with eyes! You get a dying quail, just one more dying quail a week and you're in Yankee Stadium.” – Crash Davis (Bull Durham, 1988)

That, ladies and gentlemen, is BABIP in a nutshell. Sometimes it really is better to be lucky than good. One of the primary ways to measure the role luck plays in hitting and pitching is BABIP. That being said, there is much more to BABIP than just luck. Understanding BABIP and what goes into it can be very important for fantasy players looking for an advantage over their league mates.

What is BABIP?

BABIP is an acronym for batting average on balls in play. BABIP measures how often batted balls fall for hits. One way to think of BABIP is batting average if we take out strikeouts. BABIP is only measuring balls put in play.

For the purposes of BABIP, think of balls in play as batted balls that a fielder could conceivably make a play on. A home run is not considered a ball in play. That leads us to the formula for calculating BABIP. BABIP = (H – HR)/(AB – K – HR + SF).

So as we stated above, home runs do not count, and neither do strikeouts, so both are subtracted from the hits and at-bats. Sacrifices do count, however, so they are added to at-bats.

How do we use BABIP for fantasy?

The lazy answer is that you look for players with an extreme BABIP (either high or low) and expect that player’s BABIP to normalize going forward. The league average BABIP is around .300, and if we didn’t know anything else, we could expect an extreme BABIP to move closer to .300 over time.

That approach can even work, to some degree. All else being equal, BABIP does tend to regress to the mean over time. There are problems with this approach, however.

BABIP is not entirely a function of luck. Players, especially batters, do have some control over whether or not they have a high (or low) BABIP. Before you assume a player’s (or team’s) BABIP has changed largely due to luck, you have to make sure nothing else has changed that could account for the change in BABIP.

This obviously requires a greater understanding of BABIP and what contributes to it. Once we understand the factors that can contribute to BABIP, we can look at those factors to try to make sense of a player’s BABIP.

In the end, assuming a player’s circumstances are largely unchanged, we would expect that player’s BABIP to regress to his career average, not the league average. Starling Marte has a .346 BABIP through 3108 career at-bats. If we are projecting his BABIP for 2018 we should start at .346, not the league average of .300. If he has consistently been better than league average in his career, the odds are he will continue to do so going forward.

Before we get into the factors that contribute to BABIP, there are a few important baselines we can establish for fantasy players as they look at BABIP. As we mentioned above, the league average for BABIP is around .300. No one has ever had a career BABIP over .380, and the highest career mark for an active player is Domingo Santana at .360. Conversely, Joey Gallo has the lowest active BABIP at .256. If you see a BABIP that falls below .260 or above .360, it should probably cause you to raise an eyebrow or even two. 

The other important rule of thumb for fantasy players with regards to BABIP is that hitters have more control over BABIP than pitchers do. Hopefully, this will become clearer once we look at the various factors that contribute to BABIP. Once the pitcher throws the ball, the result is (please forgive the pun) out of his hands. What happens next is up to the batter, the fielders and the fates.

What contributes to BABIP?

There are five main factors that contribute to BABIP. They are: the type of contact, the quality of contact, the placement of contact, ballpark and luck. Let’s take an in-depth look at each one in turn.

  1. Type of Contact

Not all batted balls are created equal. Line drives go for hits more often than groundballs, which are hits more often than flyballs. This should make sense intuitively, even if you have never really thought about it or looked at the numbers. Let’s illustrate the point with a brief thought experiment.

Picture yourself at home on your couch on a warm summer evening watching your local baseball team on television. Your favorite player comes to bat, and on the first pitch, he hits a line drive to the left side. You lose sight of the ball for a split second while the broadcast changes to a different camera shot, and the next thing you know the line drive has been caught by the shortstop. How do you react? Are you surprised? Perhaps disappointed?

Now, picture the same exact scenario, except instead of a line drive, the batter hits a ground ball, or a fly ball, that goes for an out. Are you disappointed? Are you at all surprised? That is because we know from watching hours of baseball that line drives go for hits more than other contact. That is why for years and years Little League coaches have tried to get their players to hit line drives.

What this means for our purposes is, in general, players who hit a lot of fly balls will have a lower BABIP. Players with a lot of line drives do better, especially if they combine those line drives with a good number of groundballs.

One of the reasons groundballs are better for BABIP than flyballs is groundballs give the runner an opportunity to beat out the throw for a base hit. This is one of the biggest reasons guys like Odubel Herrera , Christian Yelich , César Hernández and Austin Jackson are near the top of the career BABIP list for active players. Mallex Smith , with a 51.9% groundball rate and a .349 career BABIP, could wind up being a similar player over his career at least until he starts to slow down.

  1. Quality of Contact

This is another factor that is obvious when you think about it. The more often you hit the ball hard, the more hits you will get in the long run. Over the course of a few months or even an entire season you may hit the ball hard with nothing to show for it, but if you keep that up long enough, you will eventually get rewarded.

It makes some degree of sense that Aaron Judge is third among active players in BABIP and second in hard hit percentage. It would be reasonable to look at young hitters with high strikeout rates like Miguel Sano , Judge and Domingo Santana and conclude their batting averages will drop significantly in 2018. That being said, if they keep hitting the ball hard consistently, they may not suffer much of a drop in batting average even if their strikeouts remain the same. Kris Bryant looked like a prime candidate for batting average regression after he had a .275 average, .378 BABIP and 30.6 K% as a rookie. He now has a .285 career batting average, and while much of the credit for that belongs to a lower strikeout rate, it also helps that he continues to make hard contact.

In addition to hard hit percentage, another way to possibly measure quality of contact is average exit velocity. Tommy Pham finished 13th in average exit velocity and 21st in BABIP last season. Neither hard hit percentage nor average exit velocity is a perfect measure of quality of contact, but they can give you a pretty good idea, especially when you consider the type of contact as well.

  1. Placement of Contact

As Wee Willie Keeler famously said, the key to batting success is to “hit it where they ain’t.” In today’s game, that mostly means hitting the ball away from the shift. Left-handed batters who are pull heavy are easier to defend, so it shouldn’t come as a surprise when someone like Joey Gallo has one of the 10 lowest BABIPs in baseball.

For pitchers, I like to think of placement of contact in terms of defense. Groundball pitchers rely on their defense quite a bit, as do flyball pitchers in big ballparks. A groundball up the middle might be a single against the Orioles but a double play against the Cubs. This is why it can be smart to consider team defense when evaluating starting pitchers.

  1. Ballpark

It probably isn’t a coincidence that three of the 10 active pitchers with the highest career BABIPs have called Coors Field home for significant portions of their careers. Much like fielding and positioning are important for BABIP, so are a ballpark’s dimensions. Because Coors Field has such a big outfield, a lot of flyballs and line drives drop in for hits that would probably be outs in other ballparks.

Jon Gray allowed a .336 BABIP at home this season and a .308 BABIP on the road. If he ever found himself on another team, he might significantly lower his BABIP.

  1. Luck

Don’t think luck plays a role in batting average and BABIP? Ask Crash Davis: “Do you know what the difference between hitting .250 and .300 is? That's 25 hits...25 hits in 500 at bats is 50 points...ok. There's 6 months in a season. That's about 25 weeks. That means if you get just one extra flare a week, just one. A gork, you get a ground ball, you get a ground ball with eyes! You get a dying quail, just one more dying quail a week and you're in Yankee Stadium.” – (Bull Durham, 1988)

One extra lucky hit per week can make a huge difference by the end of the season, and you probably wouldn't even notice without looking at BABIP. In Moneyball (The book by Michael Lewis, not the movie), Scott Hatteberg has a couple of quotes that illustrate why it is foolish to ignore the role luck plays in batting average.

Talking about his time with the Red Sox, Hatteberg said ”I’d have games when I’d have two hits and I didn’t take a good swing the whole game,” he said, “and it was like ‘Great game, Hatty.’” As he told it, his experience was different in Oakland. “Here I go 0 for 3 with two lineouts and a walk and the general manager comes by my locker and says, ‘Hey, great at bats.’”

As fantasy players, you want to target the batters who will have great at-bats. If you have enough great at-bats, you will eventually get good results, even if you can go an entire season without seeing them. With that in mind, let’s look at a couple of blind resumes.

Player A6750.3040.3540.5525.2%17.60%0.33018.2%45.3%36.4%17.9%15.8%43.7%40.5%
Player B5530.2650.3250.4736.7%19.70%0.29421.2%44.2%34.6%16.1%17.2%44.9%37.9%

Player A is José Abreu in 2017. Player B is José Abreu in 2018. Abreu’s .265 batting average and .294 BABIP in 2018 were career lows. Prior to 2018 he had never batted below .290 and never had a BABIP below .327. His 37.9 percent hard contact rate is the second-highest of his career. Barring a physical decline in his age 32 season, I expect Abreu’s luck to turn around.

We have mentioned a few times already that pitchers’ BABIPs tend to be influenced heavily by the defense behind them. They are also influenced quite a bit by luck. So often, a ball will sneak through the infield or split the outfielders that would have been caught, perhaps rather easily, if it was a foot or two in either direction. Those simple twists of fate can add up over time.

Now that we have discussed BABIP, how to think about it for fantasy and the factors that contribute to it, it is time to take a closer look at five notable BABIPs from 2018. These are players who could be difficult to evaluate for 2019, but you get a more complete picture once you dive into their 2018 numbers.

José Ramírez

Ramirez was one of the best hitters in baseball in 2018 despite having the 12th lowest BABIP among qualified batters. Ramirez’s BABIP cratered to .252 after he had a .319 BABIP in 2017 and a .333 BABIP in 2015. His career-low BABIP was .232 in 2015, so while I expect some bounce back in 2019, it isn’t a fait accompli. Ramirez’s 45.9 percent flyball rate was by far the highest of his career, and while it led to a career-high 39 home runs, it almost certainly helps account for the low BABIP as well. I think we should probably expect some home run regression and BABIP regression for 2019.

Francisco Lindor

Here is Francisco Lindor ’s BABIP in his four MLB seasons, beginning as a rookie in 2015: .348, .324, .275, .279. Like José Ramírez , Francisco Lindor has seen a spike in his flyball rate, from under 29 percent in each of his first two seasons to over 39 percent in each of the next two. His days of batting .300 are probably a distant memory, though I doubt fantasy players will complain much.

Nick Pivetta

Pivetta allowed the highest BABIP in baseball last season at .326, which helps account for his 4.77 ERA and 3.80 FIP. Only Jon Gray , who calls Coors Field his home ballpark, had a higher difference between his ERA and FIP.

Lucas Giolito

Lucas Giolito had the 11th lowest BABIP allowed in baseball last season, but he still finished with a 6.13 ERA. I suppose no amount of BABIP luck can overcome a 1.39 K/BB rate.

Patrick Corbin

Corbin was probably the breakout starting pitcher of 2018, finishing with 246 strikeouts and a 3.15 ERA. His .302 BABIP allowed was the seventh highest among qualified starters but his lowest since 2013. Corbin allowed a 41.7 percent hard contact rate in 2018, surpassing his previous career-high of 38.5 percent. It’s probably fair to expect a BABIP around or slightly above his career average of .311, but I wouldn’t be shocked if it actually falls below .300 in 2019, assuming his hard contact rate falls.

Predicting how a player’s BABIP will change from one year to the next is inexact at best, but the ability to do so can be a great asset for fantasy players. Remember, before you draw a conclusion regarding a player’s BABIP, you have to look at how he got there so that you can hopefully figure out where he might be going.