Wide receiver Breshad Perriman is out indefinitely,according to a report from NFL Media's Ian Rapoport.
The Ravens' first-round pick re-injured his PCL during pre-game warmups last week and had arthroscopic surgery performed by Dr. James Andrews, Rapoport reported.
The surgery is a tough setback for Perriman, who went down with a knee injury on the opening day of training camp. Perriman appeared to be making progress, as he returned to practice last week for the first time since July 30.
He was running a series of routes during Sunday's warmups, but pulled up lame trying to track a deep ball. He then limped around the field for several minutes and didn't run or jog any more during warmups.
When asked early this week about a possible setback, Head Coach John Harbaugh said: "I have no idea what you're talking about."
Perriman did not practice at all this week and had already been ruled out of Thursday night's game in Pittsburgh.
With Perriman reportedly out for the foreseeable future, the Ravens will continue to go with Kamar Aiken, Marlon Brown and Michael Campanaro as the complementary pieces to veteran Steve Smith Sr.