Granderson’s Just Fine

Plucked out of the University of Illinois at Chicago in the 3rd round of the 2002 draft, Tigers center fielder Curtis Granderson has surpassed all expectations.

Since reaching the big leagues for good in 2006, Granderson has blended a keen batting eye, surprising pop and fleet feet to become one of the most productive players patrolling the middle garden. The lefty batter posted 3.9 Wins Above Replacement in 2006, +7.4 in 2007, +3.8 in 2008, and +2.9 in 2009 with a few games yet to be played.

Granderson enjoyed a banner year in 2007, compiling a .395 wOBA which lead all center fielders. That performance came with a .362 BABIP and a stunning 23 triples, though, so it wouldn’t have been reasonable to expect a repeat performance the following season. Curtis was still highly productive in 2008, however. With his BABIP down to .317, Granderson posted a .374 wOBA. Only Josh Hamilton, Grady Sizemore and Carlos Beltran boasted better offensive numbers.

In 2009, though? Granderson appears to be in the midst of a disappointing campaign. Curtis batted .280/.365/.494 in ’08, but he’s down to .246/.326/.445 this year, with a .337 wOBA. What gives? What’s different in 2009?

Evidently, not much. Take a look at some of Granderson’s key offensive barometers from 2008 and 2009:

Walk rate: 11.4 BB% in ’08, 10.4 BB% in ’09
K rate: 20.1 K% in ’08, 22.8 K% in ’09
Isolated Power (SLG%-BAVG): .213 in ’08, .199 in ’09
Outside Swing% (MLB avg. is about 25%): 19.8% in ’08, 20.1% in ’09
Contact% (MLB avg. is about 81%): 79.6% in ’08, 80.1% in ’09

Granderson has walked slightly less while punching out a little more, popping a couple fewer extra base hits as well. But there’s nothing here that would portend to a 37-point dip in wOBA.

What’s the problem, then? Granderson’s BABIP, as mentioned before, was .317 in 2008. In 2009, that figure has fallen all the way to .276.

It would be easy to simply declare, “he’s been unlucky” and move on. But thanks to some outstanding work done by Chris Dutton and Peter Bendix on what factors influence BABIP for hitters, we can go beyond such a cursory statement.

For a while, most analysts attempting to find a batter’s expected BABIP would used a formula like “line drive percentage + .120.” The premise makes some sense, as line drives fall for a hit about 74 percent of the time.

However, Dutton and Bendix included many more variables in their XBABIP study. Taking items such as line drive rate, batting eye (BB/K ratio), speed score and pitches per PA into consideration, Dutton and Bendix’s XBABIP model yielded very promising results. Their study indicated a 59 percent correlation between actual and predicted BABIP, compared to just 18 percent for the “LD + .120” concept.

Luckily, Derek Carty of The Hardball Times came out with a simple XBABIP tool based on Dutton and Bendix’s work. The tool takes a hitter’s AB’s, HR’s, K’s, SB’s, LD%, flyballs, pop ups and grounders and spits out an expected BABIP.

According to the XBABIP tool, Granderson’s BABIP should be around .303. That’s somewhat lower than his 2008 figure, because Curtis has hit more flyballs (which have a lower BABIP) and he has popped out more often (pop ups are near automatic outs):

2008: 40.7 FB%, 5.0 infield/fly ball%
2009: 48.8 FB%, 12.2 infield/fly ball%

Even so, Granderson’s line would be .273/.353/.472 in 2009 if his BABIP were .303 instead of .276 (and that’s assuming all additional hits were singles). That equates to a wOBA of about .369. Not quite at his 2008 level, but pretty close. As an additional bonus, Granderson has swiped 20 bags in 26 attempts this season, after limiting his running in ’08 (12 SB, 4 CS).

Granderson’s 2009 line is misleading. He had a career year in 2007, and has settled in as a .370 wOBA-type hitter over the past two seasons. Odds are, he’ll be undervalued on draft day heading into the 2010 season. Granderson is still the same all-around threat.