Harden returns to Oakland, but where's his stuff?

On Wednesday, the Athletics agreed to a deal with Rich Harden worth about $1.5 million.  Harden began his career with the A's in 2003 and remained in Oakland until a 2008 trade sent him to the Cubs.  He signed with Texas in 2010 and turned in a sub-replacement level performance that included two trips to the DL; his strikeouts plummeted and his walks climbed to a career high in 2010  Clearly, the Athletics will be hoping he can return to his 2008-2009 form, in which averaged 11 strikeouts per 9 innings over the 289 innings he pitched during those two years.  

Harden's calling-card has always been his ability to get the strikeout; his control has never been very good (career 4.16 BB/9), and over the course of his career he's been below average at getting ground balls (39.7% overall with no season over 40% since 2006).  He's also not very durable, as he hasn't thrown 150 innings or reached 30 starts in any season since 2004.  In 2010, his K/9 rate dropped from 11, where it was in 2008 and 2009, to 7.3.  The two aspects of his game that were clearly affected the most were his velocity and, maybe not unsurprisingly, his previously superb ability to miss bats.  The charts in this post will only focus on his four-seamer and changeup, which pretty much make up his entire arsenal.  I counted 5 two-seamers in 2008, just 2 in 2009, and 24 in 2010 (1025 four-seamers in 2010, which makes for a ratio of about 43:1).  I feel pretty good about the fastball classifications, but there may be a few more two-seamers from 2010 that were lumped in with the four-seamers.  The charts below shows the velocity distribution by year for Harden's four-seamer (top) and change (bottom).

If the chart for the fastball looks kind of funky, that's because it is.  Harden throws his fastball at a lot of different speeds - at the beginning of a game, he'll often be in the mid-high 80s and work his way up to the mid 90s.  You probably also noticed that Harden's fastball was significantly slower in 2010 than it had been previously.  Pitching half of his games in Texas, where the gun was slow, has something to do with that, but it doesn't constitute a difference that big.  

Now, as we know, limited velocity means nothing if you can still find a way to fool batters.  The big problem for Harden last year was that for the first time in his career, his whiff rate (.197) dropped below the league average.  As I mentioned before, without an ability to prevent walks or home runs, the strikeouts and whiffs become extremely important, and in this category Harden went from elite in 2009 to mediocre in 2010.  To illustrate his decline, here are the cumulative whiff rates for his four-seamer and changeup for the three seasons dating back to 2008.  For context, consider a league average four-seam fastball whiff rate of around 16% and a league average changeup whiff rate of around 30%.   

As you can see, both of his pitches surrendered a lot more contact in 2010 than they did in 2008 and 2009 - the changeup was ridiculous for the two years, with a whiff rate near 50%, and it plummeted to just 30% this year.  The fastball was also considerably above average and dipped significantly this year.  

We all know what Harden is capable of, and it wasn't that long ago that he was a dominant strikeout demon.  But can he regain his pre-2010 form?  The A's certainly hope so.