"He felt great and everything, but not real efficient," Cubs manager Dale Sveum said Sunday. "Right now, we have to get him built up to get to the fourth, fifth and hopefully sixth inning."
Garza, who will be in Chicago this week when the Cubs return for a three-game homestand against the Rockies, will make his next start for Triple-A Iowa.
When Garza is ready to return, it will be tough to eliminate one of the starters from the mix. Edwin Jackson is the only pitcher who has struggled, and he's not a candidate to move to the bullpen.
"It ain't going to be easy," Sveum said about moving one of the starters. "Part of it, sometimes, when you have these decisions ... it's a good problem to have, but for the individual, nobody deserves it. They're pitching perfectly fine. It isn't going to be the easiest thing to do."
Garza is working his way back from a strained left lat suffered in mid-February during live batting practice. The plan on Saturday was to have Garza throw 65-75 pitches. He needed 30 pitches to get through the first inning.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.