Rockies place reliever Roberts on the 15-day DL

DENVER -- The Rockies placed left-handed reliever Ken Roberts on the 15-day disabled list with left elbow inflammation before Saturday's doubleheader versus San Francisco. As expected, Colorado also activated right-hander Brooks Brown from the 15-day DL.

Colorado manager Walt Weiss said there's always a level of caution with elbow problems but added that he's "not overly concerned" about Roberts' injury. The left-hander said he'd had some pain "for the past week," but it didn't become a problem in a game until Friday's outing against the Giants.

"Just throwing in throwing programs and stuff -- there was some pain there," Roberts said. "The next day, it got a little better -- and after that, it was just kind of a little bit of pain there. So I've kind of been dealing with it for a week or so now."

Roberts lasted just two-thirds of inning in Friday's 11-8 loss, surrendering three runs and four hits while walking one. It was his second shortest outing of the year and represented the most runs he's given up in a single appearance this season.

"Just warming up in the 'pen, I couldn't ever get there -- just right mentally and physically -- so it kind of just carried over," Roberts said. "So, obviously, I can't help the team with that."

Brown, meanwhile, will jump right back into his original role as a reliever Weiss feels confident using for more than one inning. Right shoulder inflammation landed Brown on the DL.

Chatwood progressing

• Rockies pitcher Tyler Chatwood, recovering from last summer's Tommy John surgery on his right elbow, will take the next step in his rehab on Sunday, when he starts throwing breaking pitches. Chatwood, 25, went 8-5 with a 3.15 ERA in 20 starts for the Rockies in 2013, but injuries limited him to four starts (1-0, 4.50 ERA) last season. Chatwood wants to pitch in the Majors by season's end, but said he is being careful not to push his rehab pace.

"It'll still be a while before I get into games," Chatwood said. "We're not setting any exact timetables, because I don't want to let down if I don't hit that timetable. But there are no setbacks so far."