We had some tests done this morning, which suggests the recovery would require a DL stint," manager Bryan Price said before Wednesday night's series finale. "He's going to be working on rehab for the next couple of weeks and hopefully be ready to go after his DL stint."
Cincinnati recalled outfielder Brennan Boesch from Triple-A Louisville, and also selected the contract of reliever Sam LeCure. Reliever Dylan Axelrod was also optioned to Louisville while reliever Nate Adcock was transferred to the 60-day DL.
During the Reds' 3-1 loss on Tuesday in 13 innings, the Royals' Alcides Escobar drove a line drive to right-center-field to lead off the 11th. Hamilton made a nice effort to dive for the ball and snare it on one hop to prevent it from going through the gap. Then, Hamilton got up and made a great throw that nailed Escobar at second base.
"After that throw, he said 'it did not feel good,'" Price said.
Hamilton, who is batting .226/.272/.290 this season with 54 steals in 107 games, exited the game before the top of the 12th inning.
"It's not a two- or three-day deal," Price said. "With a four-man bench, there's just no way to be able to weather a week or 10 days with a three-man bench or cutting our bullpen back to seven and going to more of a four-man bench. It just made sense to DL him. I think it will take the bulk of that 15 days to get Billy back on top of his game and hopefully that's what happens. There is no guarantee he will be ready after the 15 days, but we're confident at this point, he will be."
Boesch returns to the big leagues after batting .331 with four home runs and 28 RBIs for Louisville. He was sent down on June 15 after hitting .125 in 32 games earlier this season for the Reds.
Jason Bourgeois started in center field on Wednesday vs. Kansas City, but Price also expected to mix-and-match players with Marlon Byrd and Boesch also likely to get starts there. There could also be prospects eventually called up to get chances.
"In our position, especially as the rosters increase in September, it's going to be important to see guys in our system moving towards playing good baseball for the remainder of 2015," Price said "But also getting an idea of what we may have in the mix for 2016."
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, follow him on Twitter @m_sheldon and Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.