Another Look at Arod’s 2010 Peformance Against Lefties

This post originally appeared on The Captain’s Blog and is a followup to one published at both the Yankeeist and Fangraphs’ Community Forum.

Over at the Yankeeist, Larry Koestler took a look at one of 2010’s most curious mysteries: Alex Rodriguez’ shockingly poor performance against left handed pitchers. Using pitchFX data, Koestler concludes that the pitch selection of opposing southpaws (i.e., fewer four seamers and more cutters, two seamers and sinkers) contributed to Arod’s struggles (while also conceding the limited sample size), but could the answer be much more benign?

Alex Rodriguez’ LD% vs. BABIP, 2004-2010

Note: Columns represent wOBA; lines represent BABIP
Source: Baseball-reference.com and fangraphs.com

What jumps off the stat page most about Arod’s 2010 season is his BABIP of .212 against left handers, which is by far his lowest rate in either split since joining the Yankees. Although it may be too easy to attribute all of Arod’s struggles against lefties to bad luck, his very low batting average on balls in play seems to suggest that fortune wasn’t always on his side. Then again, it’s also possible that Arod’s lower BABIP resulted from weaker contact, and, in fact, that seems to be the case. As a Yankee, Arod’s line drive percentage against lefties had ranged from 14.2% in 2004 to a whopping 26.4% in 2009 before falling to 12.10% last year. More specifically, Arod’s line drive percentage declined the most against lefties’ cutters, two seamers and sinkers…the same three pitches identified by Koestler.

Alex Rodriguez’ LD% by Pitch Type, 2009-2010

Note: Columns represent number of pitches; lines represent LD%
Legend: CH – Changeup; CU – Curveball; FA – Fastball; FC – Fastball (Cutter); FF – Fastball (Four-seam); FT – Fastball (Two-seam); SI – Sinker; and SL – Slider
Source: Baseball-reference.com and joelefkowitz.com

So, have left handers found a way to combat Arod by throwing pitches that he can not drive? Or could the answer be more about who is throwing those pitches than the selection itself? In 2010, Alex Rodriguez batted 189 times against lefties, including 49 times, or 26%, against David Price, Johan Santana, Ricky Romero, Cliff Lee, and Francisco Liriano. Against that cross section, Arod batted .114/.204/.182. In 2009, Arod faced that quintet only 37 times, or 21%. Interestingly, however, he did quite well against this group, posting a solid line of .241/.405/.448. When you consider how Arod handled the league’s best lefties in 2009, it’s no surprise he had such an outstanding season against southpaws (in both years, Arod excelled against Jon Lester).

Alex Rodriguez’ PAs vs. Select Top Lefties

Player	2010	2009
David Price	13	9
Cliff Lee	10	11
Francisco Liriano	10	6
Ricky Romero	9	9
Johan Santana	7	2
Total	49	37

Source: Baseball-reference.com

The knee jerk reaction would be to suggest that Arod’s skills are in decline and, therefore, he can no longer hit the league’s best lefties. However, a closer look at the five lefties who dominated Arod in 2010 reveals that they all improved their performance against righties by varying degrees from 2009. In other words, Arod’s struggles last year may be more about them than him.

Select Top Lefties vs. RHB, 2009-2010

Source: Baseball-reference.com

Often times, the desire to pinpoint the reason behind an outlier can lead to a variety of plausible theories. However, the small samples involved make all but the most glaring conclusions lack the necessary significance to be convincing. As a result, although we know Arod must hit better against lefties in 2011, it remains to be seen whether that means he’ll need to figure out how to handle a lefty’s cutter, or just how to handle David Price.