Washington: Washington Redskins quarterback Robert Griffin III faces a spell on the sidelines after being concussed in a preseason victory over the Detroit Lions, it was confirmed on Friday.

Griffin left the game in the second quarter of the Redskins’ 21-17 win on Thursday after suffering a torrid time at the hands of Detroit’s defence.

Redskins head coach Jay Gruden said it was unclear how long Griffin would be out of action, or whether he would recover in time for next Saturday’s preseason game against the Baltimore Ravens.

“We’ll have to see,” Gruden said. “I would imagine, depending on how long he is out, he is still going to be our starter. We have to wait and go through the whole process and see how he recovers; see how fast he recovers. I have no idea as far as the third preseason game, fourth one, right now.”

A Redskins executive official told ESPN on Friday Griffin was “fine” and could be fit to face the Ravens next week.

“But [we] still need to make sure he is right,” the official added.

Under NFL guidelines for dealing with cases of concussion, there is no specified time frame for a player’s return.

Griffin will need to undergo and receive a further assessment before being approved to return by an independent neurologist.

Griffin needed prolonged treatment after being buried by Lions defensive end Corey Wootton following a fumble.

He had earlier been sacked three times and fumbled twice, losing one.