Stephenson was placed on the 10-day disabled list Sunday due to a right shoulder contusion.
Although Stephenson managed to navigate 5.2 innings during his previous start in Pittsburgh, he actually injured his shoulder diving for a ball in that contest. However, John Fay of WCPO.com doesn't believe the injury is very serious, meaning that the right-hander likely will only miss one turn of the rotation. To replace him on the active roster, Lisalverto Bonilla was called up from Louisville.