DENVER -- The Rockies are concerned that right-hander Tyler Chatwood's back injury that flared up Sunday could force him to the disabled list.
Chatwood labored with "manageable" tightness through four innings and allowed six runs in a 7-6 loss to the Phillies. He missed two starts with a back strain earlier this season during a 15-day disabled list stint in late June.
"We have decisions to make there," Rockies manager Walt Weiss said. "I think the next couple days will tell us a lot. We do have an off-day coming up that we can work with, but it's a conversation that we need to have today to decide in the next couple days."
After a three-game series against the Nationals that began Monday, the Rockies have a day off Thursday before a three-game set against the Cubs.
By skipping Chatwood once in the rotation, the other four starters could remain on normal rest, although the club could prefer to give the other young arms an extra day off. Rookie Jon Gray, for example, has allowed 15 runs in his last two starts spanning seven innings after tossing six straight quality starts.
But if Chatwood needs more than one start skipped, the Rockies could turn to long-reliever Chris Rusin or recall someone to start from Triple-A Albuquerque.
Right-hander Eddie Butler made nine starts for Colorado this season with a 6.85 ERA, but he's been excellent for Albuquerque after making a delivery adjustment, throwing two straight scoreless starts spanning 15 innings. He is slated to pitch Monday and would be able to fill Chatwood's rotation spot on normal rest.
Right-hander Jeff Hoffman, the Rockies' No. 3 prospect, according to MLBPipeline.com, is another potential option after tossing five scoreless innings with one hit, one walk and nine strikeouts on Sunday. However he and No. 8 prospect, left-hander Kyle Freeland, would require a 40-man roster spot to be cleared.
"We have to look at all the different options and scenarios and come to a conclusion," Weiss said. "[A DL stint is] possible, but again it has a lot to do with how he's evaluated in the next couple days."
Reynolds undergoes surgery
First baseman Mark Reynolds underwent surgery Monday to remove a fractured hook of the hamate bone in his left hand. The procedure was performed by Dr. Randy Viola in Vail at The Steadman Clinic.
Reynolds was removed from Thursday's game when he felt pain on a swing-and-miss. He is expected to miss four to eight weeks.