PHILADELPHIA — Colt McCoy ran to avoid a sack and tried to slide as the Eagles defense rushed toward him. McCoy’ planted his right leg into the turf and the lower part of the leg and ankle viciously whipped into safety Malcolm Jenkins’ knee.

The Washington Redskins know a thing or two about serious injuries to quarterbacks — McCoy got his chance because Alex Smith suffered a broken right leg just weeks ago that has threatened his career.

McCoy just may face a similar season-ending fate in the Redskins’ 28-13 loss Monday night in Philadelphia.

He suffered a severe injury to his right leg in the nasty slide and was replaced by Mark Sanchez, who was tasked with keeping the Redskins afloat in the NFC playoff picture.

McCoy stayed in the game and completed two short passes before limping off with the Redskins trailing 7-3 to the Super Bowl champions. The Redskins said that McCoy would not return, but didn’t immediately provide details about the injury.

McCoy took over and made his second straight start since Smith was knocked out with gruesome season-ending leg injury last month against Houston. McCoy helped Washington score a pair of TDs.