Evan Royster grasps his ankle after being injured in Sunday’s second quarter. (Jonathan Newton/The Washington Post)

The Redskins will place third-year running back Evan Royster on season-ending injured reserve with a high ankle sprain, Coach Mike Shanahan said on Monday.

Royster, a sixth-round pick out of Penn State in 2011, suffered the injury on a second-quarter reception. Royster had played primarily on special teams this season, and the catch on Sunday marked his first of the season.

Royster’s injury will require more than three weeks to heal, and so the Redskins will place him on IR. Shanahan said the decision hadn’t been made as to whether Washington would fill Royster’s spot on the roster.

What’s ahead:

●  In the morning, Mark Bullock looks at the Redskins’ offense, position by position.

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