RCG Rays 2012 Preview: Desmond Jennings


We know that being a “winner” does not imply anything about how good a player is. But it stands out that before Desmond Jennings called up, the Rays were 52-46 and in the midst of a month where they were below .500. After he got the call, the Rays were 39-24 (.619) and made their charge to the playoffs. But Jennings’ stats on the season were not quite as impressive as the Rays’ record with and without him would indicate. Jennings posted a .259/.356/.449 with 9 doubles, 4 triples, 10 homers, 25 RBI, and 20 stolen bases (6 CS). But his season numbers were divided very interestingly.  In his 34 big league games, spanning from July 23rd to August 28th, Jennings posted a .354/.440/.646 line with 8 doubles, 3 triples, 8 homers, 19 RBI, and 14 stolen bases (5 CS). The final 29 games of the regular season, Jennings’ line went into a free-fall down to .154/.261/.231 with 2 homers, 6 RBI, and 6 stolen bases. But it  can’t be simply that American League pitchers figured out Jennings. How then could we explain how Jennings had a big ALDS verus the eventual AL champion Texas Rangers, posting a .333/.444/.800 line with a double and 2 home runs? The forced answer to that question would have to be sample size. But Jennings was better than his overall batting line in 2011. Let’s see what was going on behind Jennings’ stats.

The easy answer is BAbip, batting average on balls in play (which is batting average with home runs and strikeouts removed from the equation). For the first stretch we mentioned, Jennings’ BAbip was .413 while for the rest of the season, it was just .186. On the season, Jennings’ BAbip was .303, a bit above the .295 MLB BAbip. But BAbip is the random, fluctuating stat that some people make it out to be. BAbip has a lot to do with batted ball types.

Looking at Jennings’ underlying stats, something shocking instantly comes into view: just 16% of Jennings hits were line drives compared to the 18% league average. Going back to Jennings’ 2011 minor league stats from Minor League Central, Jennings’ line drive percentage at Triple-A was just 17.4% compared to the 19.5% league average. Jennings 16% line drive percentage fits right in with the expected line drive rate drop from Triple-A to the major leagues. This is not a good sign. Of the 37 major leaguers who posted a line drive rate of 16% or less, exactly one hit .300 or better, Dustin Pedroia (and he’s a special case), and just two others managed to hit .290, Derek Jeter and Yunel Escobar, who were very lucky on groundballs in 2011 and are likely due for a regression (and I’m not just saying that because I’m a Rays fan and Jeter and Escobar are both in the division). Is Jennings doomed to be a below average hitter for average?

Line drives are the boon of batting average. As I’ve quoted way too many times on this site, the MLB BAbip was .237 on groundballs, .137 on flyballs, .713 on line drives, and .392 on bunts. Line drives are by far the highest mark and it’s extremely difficult to hit for a high batting average without at least an average line drive rate (but not impossible, as evidenced by Pedroia). However, batted ball type can sometimes be deceiving. There are different varieties of each batted ball type, and players’ BAbip by batted ball type differ based on how much of each variety they hit. If a player hits harder groundballs that go for extra-base hits more often than average, his BAbip on grounders will be higher. If a player hits bullet line drives for extra-base hits, his BAbip will be higher than a player who hits line drive singles. Jennings BAbip by batted ball type was interesting in 2011. He had a .247 BAbip on groundballs and a .667 BAbip on bunts thanks to his speed and a .161 BAbip on flyballs because he hit for a ton of power on line drives, positing a .621 ISO on flyballs compared to the .357 average. But on line drives, not only did he hit so few of them which made his batting average suffer to begin with, but he also didn’t hit for any power on them. Jennings’ BAbip on line drives was just .645, and that makes sense because he posted just a .129 ISO with just 20% of his hits going for extra-bases, all doubles, compared to the league averages of .249 and 27.8%. Could Jennings have a real problem on his hands?

Sometimes numbers can be deceiving. When a player hits the ball hard, why would it matter whether it was a line drive or flyballl? Jennings BAbip on line drives and flyballs was .402. The league BAbip on liners and flyballs was .384. That speaks for itself. But can Jennings get his batting average up in 2012?

Desmond Jennings hits the ball hard for power and has blazing speed. That by itself is not enough to hit for average. But the difference between Jennings and players like Curtis Granderson is that Jennings doesn’t strike out at a high rate. Jennings struck out in 20.2% of his plate appearances in 2011, barely above the MLB average of 18.5%. His strikeout rates in the minors were even lower, coming in at 14.4% of his PA’s overall and 16.1% at Triple-A. Even at Jennings’ nadir of 2011 from August 29th to the end of the regular season, he still struck out in just 21.6% of his plate appearances. That combination of making contact, hitting for power, and speed give Jennings the ability to hit for a solid average in the major leagues. And  by the way, Jennings’ low BAbip on line drives could very well have been a fluke. Using a 1 proportion Z-test using .713 as the parameter and Jennings’ .665 mark as the statistic, we get a p-value of .202, indicating that such an extreme value occurs a just about a fifth of the time. Considering how much power we know Jennings has, he could very well hit more extra-base hits and post a higher BAbip on line drives in 2011. Even if his line drive rate will stay around the 16% mark which it was in 2011 (although we have to hope it will go up), if Jennings can post an average BAbip on line drives, it will help his batting average stay at a nice level. If we plug in a .713 BAbip for Jennings’ line drives in 2011, he would have hit .268, not great but better. He has solid if not great pure hitting ability, and he’ll show that a little more in 2012. Remember that Jennings hit .275 at Triple-A in 2011 and .278 at Triple-A in 2010. That may be the range of batting average that he tops out at in the major leagues, but with his skill set, he’ll still be a well-above average major league player.

In 2011, I predict Jennings to put up an excellent season as the Rays’ leadoff man. I’ll project a .275/.370/.465 line with 25 doubles, 11 triples, 23 homers, 70 RBI, and 45 stolen bases in 54 attempts. Especially in a depressed offensive environment like Tropicana Field, those are extremely impressive numbers. Don’t sell Jennings as something he’s not. He’ll never be a player who will hit .300 five of six years like Crawford did. But his overall skill set is just as impressive and Rays fans will enjoy having Jennings patrolling an outfield spot for years to come.