Kerry Wood had one of those seasons in 2008 that helps sign the big contract, but often the team is left wondering where the money went. In this case Wood actually was as good if not better than his numbers, but there are reasons to expect he couldn't repeat them.
Before 2008 Wood had been a successful pitcher, but as everyone knows he spend a lot of time on the DL. Looking at his numbers from 1998-2004 he only started and had the following line:
IP - 1043
K/9 - 10.43
BB/9 - 4.41
K/BB - 2.36
Since then he has missed plenty of time and started some as well as pitched in relief. He was one of our solid strikeout pitchers who had high LOB% rates. He had improved some in 2004 and his walk rate went down to 3.27 every nine innings, but then he was injured. Since moving to relief his BB/9 has been around 4 before the 2008 season, but then fell drastically to 2.44 in 2008. He still struck out 11.40 batters every nine innings and his K/BB was a career high of 4.67.
Was this real or just an outlier? Looking back at the When do stats become meaningful topic we can see that his BB/9 was only against 107 batters and not enough to have his walk rate stabilize. Although he has little history in the relief role his walk rate from 2008 still seems to lower than sustainable.
His career BB/9 is 4.28, but ZiPs calls for a BB/9 of 3.75 for the remainder of 2009. This is probably due to the relief role and more weight of 2008. Either way I think the current rate this season of 5.11 is probably high for him and he also has a high HR/FB of 18.5%. When these stabilize he should at or below his current xFIP of 4.17 for the remainder of the season.
