ATLANTA -- An MRI on Williams Perez's right shoulder revealed right rotator cuff tendinitis, Braves manager Brian Snitker said before Saturday's 8-2 loss to the Cubs.
Perez exited Monday's start against the Padres in the fifth inning, and he was placed on the 15-day disabled list two days later with what was originally identified as a right rotator cuff strain.
Snitker said there's currently no timetable for Perez's return.
"I think it's just going to be more when things calm down," Snitker said.
Since being recalled from Triple-A Gwinnett on May 11, Perez had allowed three runs or fewer in four of six starts. The Braves have won six of the right-hander's nine starts this year. They are 12-40 when anyone else starts.
"With him, I think kind of like with [Mike Foltynewicz]," Snitker said. "He's just got to back off a little bit, let things calm down and then just start the progression again."
John Gant was recalled on Wednesday to fill Perez's vacated roster spot. Snitker said Gant will assume Perez's slot in the rotation for Sunday's series finale against the Cubs. Aaron Blair will start Monday's game against the Reds on five days' rest.
Worth noting
• After being scratched from his start this past Saturday against the Dodgers and placed on the DL because of bone spurs in his right elbow, Foltynewicz has begun throwing from 90 feet. Like Perez, Snitker said Foltynewicz will likely need to throw a couple of side sessions and make a rehab start before returning.
• Shae Simmons, who is recovering from Tommy John surgery, is expected to make his sixth rehab start on Saturday when he takes the mound for Double-A Mississippi. In five outings with Gwinnett and Class A Rome, the 25-year-old hasn't allowed a run and has struck out nine batters across five innings.
• Erick Aybar is slated to play nine innings for Gwinnett on Saturday night before being activated from the DL, where he landed on May 28 because of a right foot contusion. In six rehab games, the shortstop has batted .200 (5-for-25) and stolen two bases.