PHILADELPHIA -- Cole Hamels couldn't avoid the disabled list.

Though an MRI exam on the pitcher's left elbow revealed no structural damage -- welcome news to a team in desperate need of it given a steady stream of injuries -- the Phillies placed their ace on the 15-day disabled list, retroactive to Friday. He will miss at least two starts with a mild left elbow strain and can be activated Sept. 1, at the earliest.

"We just want to make sure he gets well," assistant general manager Ruben Amaro Jr. said. "We think this is the most prudent thing to do."

Hamels had a dye placed in his left elbow for the MRI, and won't throw for at least 10 days. He hopes to be ready when eligible, so he can help the Phillies during the final month.

"Just from my gut feeling from when it occurred to the past couple days and the kind of discomfort I was feeling, I knew the best thing I could possibly do was to go get it checked out," Hamels said. "My gut instinct was that it wasn't as serious as what some people could perceive.

"It's just the discomfort ... some people can pitch through it. I just wanted to make sure it wasn't anything serious. It will be tough not making these two starts, especially since we're facing some tough teams, but knowing that I'll finish the season strong and healthy is going to be good for us."

Kyle Lohse, Jamie Moyer and Kyle Kendrick will follow Fabio Castro, then J.D. Durbin. Adam Eaton, on the DL with right shoulder inflammation, threw 35 pitches in the bullpen on Wednesday and said he would likely pitch next week against the Mets. The Phillies will find a place for him, likely pushing Castro back to the bullpen.

The Phillies filled Hamels' roster spot by activating outfielder Shane Victorino from the 15-day disabled list.