© 2013 MLB Advanced Media, L.P. All rights reserved.

6/4/2013 8:38 P.M. ET

Francis closer to return after productive rehab start

CINCINNATI -- Rockies manager Walt Weiss was happy with what he heard in the report about left-hander Jeff Francis' rehab start on Monday night for Triple-A Colorado Springs.

Francis, who suffered a slight groin strain while pitching in a win against the Cubs on May 14, threw strikes on 53 of his 80 pitches, struck out five and gave up six hits against Salt Lake City. He gave up five runs, three earned, and lasted just four frames, but defensive miscues and foul balls extended innings.

"It sounded like it went pretty well -- no physical problems," Weiss said. "When guys go out on rehab assignments, I try not to get too hung up on whatever the results were, and I think his results were pretty decent. It's a good step going forward."

According to Francis' initial rehab plan, he is scheduled to start Saturday at Reno. It's unclear if the Rockies will bring him back earlier, and have him start Saturday against the Padres instead. Righty Tyler Chatwood, the pitcher slated for that night, is dealing with right triceps soreness.

Weiss thinks fatigue may be reason for Rosario's slump

CINCINNATI -- The Rockies have recently started Yorvit Torrealba at catcher when Juan Nicasio is pitching, which they did on Tuesday, providing a rest day for slumping regular catcher Wilin Rosario.

In his last eight games, Rosario is 4-for-32 (.125) with one RBI and five strikeouts, and he has seen his batting average drop 29 points to .254.

Rosario has nine home runs, but his last one was May 18. Sometimes slumps come because players are trying to go yard in every at-bat, but manager Walt Weiss said he doesn't think that's the case with Rosario.

"When he takes his [batting practice] every day, he takes a great BP," Weiss said. "He stays in the [right-center-field] gap for most of the time, even better than most of our guys, as opposed to just going out here and seeing how far he can hit it. That's why I tend to think that hasn't been the issue, where he's going up there trying to hit home runs. His preparation has been very good."

Weiss said he noticed that Rosario was making hard outs early in the slump, but not as many lately. The manager said fatigue is a possible factor. Few catchers have the offensive abilities of Rosario, but the physical and mental requirements of the position have something to do with that.

"Wilin's a strong kid -- they don't call you 'The Bull' for nothing," Weiss said. "There's plenty of strength there, but still you've got to be careful with your catchers. They take a lot of foul balls off their toes, inside their legs and their shoulders. They get nicked up pretty good back there."

Chatwood undergoes MRI, likely to miss start

CINCINNATI -- Rockies right-hander Tyler Chatwood underwent an MRI on his right triceps Tuesday afternoon, the results of which were unknown.

The Rockies believe that Chatwood did not do extensive damage during his outing Monday night, but they've cancelled a bullpen session scheduled for Wednesday, and it looks as if he'll miss his next start.

"I don't want to commit to that right now, but I think it would probably be tough to make his next start, if he misses bullpens," Rockies manager Walt Weiss said. "We want to make sure that the next time we run him out there, he's right."

The Rockies removed Chatwood after he tossed four innings on Monday, and Chatwood said after the game he felt the injury during the third inning, and after that struggled when he tried to throw to his glove-side.

A preliminary evaluation by Rockies medical director Dr. Thomas J. Noonan found no structural damage, and he ordered the precautionary MRI. Chatwood flew to Denver on Tuesday for the test.

"I don't think it's bad," Rockies head athletic trainer Keith Dugger said. "He overextended on a pitch, kind of pinched the back of his elbow, kind of inflamed the triceps tendon a little bit. We were over-cautious and got him out of the game.

"He felt good, talking to him, and he didn't report any unusual soreness."

The Rockies will re-examine Chatwood Thursday, after they return from their current road trip.

Colorado has been cautious with injuries throughout the season. Weiss declined to speculate about the identity of the starter Saturday against the Padres at Coors Field.

Thomas Harding is a reporter for MLB.com. Read his blog, Hardball in the Rockies, and follow him on Twitter @harding_at_mlb. This story was not subject to the approval of Major League Baseball or its clubs.