LANDOVER, Md. -- As he ran to his right, Robert Griffin III did what he does best. He extended the play, then he made one. Or, rather, it’s what he did so well in 2012. It’s the sort of play that excited the fans -- and it did so again Sunday. Just before he landed out of bounds, Griffin spotted DeSean Jackson, all alone, for a long gain.

That’s what the Washington Redskins needed to see from Griffin. The next sight was not. Griffin lay in pain on the sidelines, pounding the turf. Just when he started to look like his old self, Griffin’s season might have ended.

“I think we were going to have a great day if I was able to stay out there,” Griffin said. “We thought we were on the verge of a big day. It was going to be fun.”

For his teammates it still was as Washington beat Jacksonville 41-10.

But Griffin now faces the prospect of missing the rest of the season after dislocating his left ankle. He’ll undergo an MRI at 10 a.m. Monday, but after the game Redskins coach Jay Gruden told ESPN980 that it was “sad for Robert the way his season ended.” But then Gruden retreated to what he said in his news conference, that the team would know more Monday.

Griffin was trying to stay upbeat after the game, praising teammates and his replacement, quarterback Kirk Cousins. But Griffin knew on the field that his injury was bad. He felt his ankle dislocate as he escaped a tackle attempt from linebacker Paul Posluszny. His foot got caught in the FedEx Field turf and that was that.

Griffin said he looked at his ankle after the play and it was bent in a different direction. He did not ask doctors about any timetable or the severity; he did not want to know.

“When I looked at it, it didn’t look in a great position,” Griffin said. “I knew something was wrong … It’s an excruciating pain.”

Teammates wandered over to him, with tight end Niles Paul giving him a hug and whispering words. But fullback Darrel Young anticipated a different outcome.

“I’m thinking he goes in the locker room and goes, ‘I’ll be back,'" Young said.

That, of course, is not what happened.

A few days before Sunday’s game Griffin was upbeat about the game plan and what the offense could do. It was a good matchup for the Redskins and he knew it. He was playing well early, running twice on the zone-read for 22 yards and completing two of three passes for 38 yards. Receiver DeSean Jackson couldn’t hang on to a deep ball, losing it as he was on the ground.

After an up-and-down summer and lackluster opener, the Redskins needed that from Griffin.

“He was definitely on tonight,” Redskins receiver Andre Roberts said.

They didn’t need the injury. Griffin spent all of the 2013 offseason rehabbing from knee surgery, but he missed only one game that season. There’s one approach he wants to take. Even before stepping into the interview room, Griffin was trying to look forward and stay upbeat. He wasn’t bemoaning his fate, though he was trying to make sense of things.

“You never want to get hurt,” Griffin said. “You want to be out there and available for your teammates. It’s just an unfortunate situation because it wasn’t on a hit or anything. It just happened. In moments like these, you’ve just got to keep the faith.”

It’s now Cousins’ job to guide the Redskins. Any sort of future situation will play out over the next 14 weeks and then some. If Griffin’s season is over, he’ll enter 2015 coming off his second severe leg injury in three years.

“When you get hurt and your season is cut short, it’s devastating,” Gruden said. “I’m sick about it for him. He’ll probably beat all the odds and be back quicker than anybody in the history of dislocated ankles. But now we have to move forward.”