"Obviously, it is not what I want to do, but it is what needs to be done," said Hammel, who was 8-6 with a 3.54 ERA in 18 starts. "I can't keep pitching on a bad leg and start doing things with my arm and hurting things there. Obviously, [I'm] bummed out. But it's going to be a pretty routine surgery, figure a few weeks, maybe four weeks, hopefully for the return. That'll get me back in time to still be able to help the club."