TUCSON, Ariz. — Colorado Rockies setup man Taylor Buchholz will miss at least a month with a sprained ligament in his throwing elbow.

An MRI exam Wednesday revealed the problem. No surgery is scheduled, the team said.

The right-hander had a 2.17 ERA last year, sixth-lowest in the NL.

"It will be starting up from square one, which is really frustrating for everybody," Buchholz said Thursday. "I didn't envision this coming in. At least we caught it early."

Buchholz felt pain while throwing in the bullpen before his only spring training appearance Feb. 26 against the Chicago White Sox. He threw one scoreless inning, giving up three hits.

Buchholz rested a couple of days before the team scheduled the MRI.

"I felt it was just normal kind of pains that I have had before," Buchholz said. "Usually it goes away when I get into the game. This time it was a little different."

"I threw a couple of more curveballs and it kept gradually getting worse and worse. Every curveball I threw, I felt it. The last two really didn't feel good."

Buchholz has not previously had an elbow injury. He will undergo ice and heat treatment and massage therapy before starting strengthening exercises.

Buchholz was a big part of the Rockies bullpen last season, going 6-6 with one save while making his transition from starter to reliever. He is 12-11 with a 3.38 ERA in his two years with Colorado.