Chicago Cubs right-hander Matt Garza experienced tightness in his side while rehabbing and will start the season on the disabled list, manager Dale Sveum said Sunday.

“It’s a minor setback that (he) could wind up missing two weeks to a month," he said. “Now you’re looking at him getting two (Cactus League) starts at the most.”

Garza wasn't too upset, after saying this week he did not plan to rush back just be ready for opening week.

"With the recovery rate I was on, everything felt great and it was like 'Let's go, let's go, let's go,'" he said. "It's just a body's way of saying it's just going to take a little more time. It's not a setback, but just came to the realization that mind and body are (going) too fast. It's fine. Yeah, I'm not on pace now to open up, but I'm going to keep pushing, keep trying to get there."

Sveum said Garza could be out until May.

"Could be," Garza said. "But that's not what I'm planning. I don't sit back and let things happen. I try to make them happen."