Jay Gruden concerned with Perry Riley's knee

Redskins coach Jay Gruden said he’s concerned with linebacker Perry Riley's health and he’ll undergo more tests Wednesday to determine the severity of his injury.

Riley sprained his left medial collateral ligament in the second half of Monday’s 27-17 loss to Seattle. He was replaced by linebacker Will Compton, in his first season after spending last year on the practice squad.

Riley has had lapses in coverage this season, as well as in the past. The coaches have been high on Compton, with one coach confident this summer that Compton could step in to start if necessary. But it would also leave Washington with two young inside linebackers. Riley has started 61 consecutive games; fellow inside linebacker Keenan Robinson has started five. Compton has played 21 snaps from scrimmage.

No other Redskins player suffered a significant injury, Gruden said, adding that left tackle Trent Williams, who played with a partially dislocated kneecap, “came out pretty good.”