Right-hander Micah Owings, on the disabled list since July 27 with a tight right shoulder, was activated.
Cueto is 8-10 with a 4.61 ERA in 24 starts. Owings, 6-11 with a 5.35 ERA, is scheduled to make the start Friday at Pittsburgh for Cueto.
The Reds also sent third baseman Scott Rolen to Triple-A Louisville on a rehab assignment. Rolen has been on the disabled list since Aug. 11 with a concussion, the result of getting hit in the head by a pitch on Aug. 2. Rolen has hit .143 with a home run and two RBIs in four games since being acquired from Toronto Blue Jays on July 31.