They also might get opening day starter Aaron Harang back next week, too.
The NL Central leaders are tinkering with their staff, trying to get ready for a strong September run while protecting their young pitchers from overuse. Leake was one of their concerns, appearing to wear down while his innings piled up lately.
The 22-year-old pitcher made the jump directly from Arizona State to the majors, winning the final spot in the rotation during spring training. He was among the NL's top rookie pitchers during the first half of the season, winning five in a row while leading all NL rookies in innings pitched.
He was less effective in August, prompting the Reds to move him to the bullpen to cut down on his innings. He got hit hard in his two relief appearances -- eight earned runs in 2 2/3 innings -- so the Reds sent him for a shoulder exam.
"We think it's better for him," manager Dusty Baker said. "He still may be eligible for down the stretch and the playoffs. He's not throwing the ball where he wants to throw it, even though he has good velocity. He's been examined by the doctors. Since he has a little shoulder fatigue - we were going to try to do something with him anyway. We think now it's time for him to get on a strengthening program and not worry about pitching as much."
Leake went 8-4 with a 3.78 ERA in 22 starts. The Reds expect him to be back in September, giving them another option.
Harang has been sidelined by back spasms since July 6. He had no problems during a rehab stint in the minors.
"I haven't had any issue with the back at all," Harang said. "I think that's the last thing on my mind when I'm pitching now.
"The hardest part right now is just that ample amount of down time, not being able to get out there and participate. You have to go out there and be more of a cheerleader. After a little while, you want to be back out there. You don't want to be the cheerleader anymore."
Harang gave up 14 hits and 11 runs in 11 innings during two starts for Triple-A Louisville, but wasn't concerned about the results.
"I went down there and worked on building my endurance up," he said. "You want to get that feeling back and not worry about the outcome. Pitching is about feeling."
The Reds called up utility player Juan Francisco from Louisville to take Leake's spot temporarily, with outfielder Laynce Nix bothered by a sore left ankle that he twisted on Monday. Francisco is in his third stint with the Reds.
The Reds also needed an extra position player because second baseman Brandon Phillips is bothered by a sore right hand, hit by a pitch in San Francisco on Wednesday. X-rays were negative. He was out of the lineup on Friday for the opening game of a weekend series against the Chicago Cubs.
"Hopefully he'll be back in a day or two," Baker said.