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Edwin Jackson’s Two Seasons

During the first half of the year Edwin Jackson looked like a different pitcher. For years his hype had preceded his performance, so much so that you began wondering whether he was ever going to figure it out, or simply burn out like Daniel Cabrera. Then the first half of 2009 happened and wham. Jackson even made his first all-star team. Well, his second half numbers have raised a new question: was Jackson of the first half simply a fluke?

Take a look at his strikeout and walk ratios independent of innings, home runs, and hits:

K%
2006-2008: 15.3%
2009 first half: 20.0%
2009 second half: 16.6%

Unintentional BB%
2006-2008: 10.8%
2009 first half: 7.0%
2009 second half: 8.0%

Where both rates saw massive improvements in the first half, they’ve basically regressed to the mid-points of 2006-2008 and the 2009 first half over these past few months. Meanwhile, Jackson only allowed 10 home runs in 18 starts during the first half and has allowed 15 in his 12 second half starts; this in conjunction with a BABIP that was below .250 in the first half and over .310 in the second.

So it’s no surprise that Edwin’s ERA in the second half is near 4.8 while his first half ERA was 2.52. His FIP is still lower than recent years but his tRA is actually his second best since 2006 – with his best coming in 2006, and we know how the next few years turned out. Jackson has seemingly improved, but not to the degree many seemed to think during those early months.