When Dan Duquette traded Jeremy Guthrie to the Rockies for Jason Hammel and Matt Lindstrom, a lot of Orioles fans were not particularly pleased. "Guthrie's the team's only real starter." "He's the O's #1 guy." And so on. Hammel didn't do much of anything in Tampa Bay, and then followed up two solid seasons in Colorado with a down year in 2011. I thought that Guthrie and Hammel could be expected to be about equally good in 2012, but that Hammel had a better chance of providing the O's with above average production. And I still ended up underestimating Jason Hammel. Boy what a difference one pitch can make.
The "fastball" combines the two-seamer with the four-seamer. Breaking them out for 2012 it's 15% and 20%, respectively. As primarily a fastball-slider guy, it's easy to see why Hammel's strike-out rate jumped so much - he started missing way more bats. The sinker and the slider tend to work well together, and he started going to the slider more often this year as he added the sinker - from ~17% of his offerings to over 22%.