Ravens first-round pick Breshad Perriman missed his 12th straight practice Monday with a knee injury. The No. 26 overall pick has been out since landing hard after a reception on July 30, but head coach John Harbaugh recently acknowledged that Perriman's injury might be more than just a bruise, according to The Baltimore Sun.

"He's got whatever they want to call it with his knee situation there," Harbaugh said. "It's not something that's going to keep him out for a long period of time, they tell me. If I was a doctor, I'd give you more. … We come out here, and we expect definitive answers on injuries from coaches. I didn't take those classes in college. I wasn't interested."

Harbaugh is still optimistic that Perriman will return during the preseason.

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"He'll be back sometime here in training camp, hopefully soon," Harbaugh added. "I hate that he's missing it, hate that he's not out here. I've got a knot in the pit of my stomach, in some ways, about it. In other ways, I know it's out of our control and I put it in God's hands and let him take care of it. To me, that's the best strategy right there."

Fellow receivers Kamar Aiken (leg) and Marlon Brown (back) were back at practice Monday while Michael Campanaro sat out for undisclosed reasons. Cornerback Lardarius Webb and guards Kelechi Osemele (foot), John Urschel (concussion) and Robert Myers (concussion) also were sidelined on Monday.

h/t: The Baltimore Sun