Zimmermann said he had problems locating his fastball, but was able to throw his breaking pitches for strikes.
"It's tough to throw in this wind, but the ones I did throw I thought were pretty good," Zimmermann said.
Unlike last year, Zimmermann will not be on an innings limit. After coming off Tommy John surgery, Zimmerman pitched just 161 1/3 innings in 2011. He is looking forward to pitching 200 innings this season.
"It's going to be a good year knowing that I'm not going to be shut down at 160. I'll be able to throw 200-plus innings," Zimmermann said. "It's definitely a good feeling."