Redskins head coach Jay Gruden on Monday said Robert Griffin III has been diagnosed with a dislocated left ankle, and has not ruled out the quarterback returning to the field as soon as this season.

"It is not a fracture and we'll know in a few more weeks as far as how long he'll be out," Gruden told reporters. "We're going to send his results of the MRI to Dr. Anderson, a foot and ankle specialist, and get it casted up and then we'll just go from there."

Griffin III's injury occurred in the first quarter yesterday's game against the Jacksonville Jaguars, as Griffin III – who scrambled out of the pocket to his right – made a last-second throw near the sideline to wide receiver DeSean Jackson.

Griffin III said he was trying to stiff arm Jacksonville linebacker Paul Posluszny when his ankle "got caught in the ground." Despite suffering the injury, Griffin III was immediately able to push off his right foot and deliver a 19-yard pass to Jackson before crumpling to the ground on the Redskins' sideline.

"When I landed, I wanted to look at my ankle because I felt something," Griffin III said after the game. "When I looked at it, it didn't look in a great position, so I kind of knew something was wrong then. So, I just called the trainers over."

As Griffin III was being tended to by the team's medical staff, backup quarterback Kirk Cousins, just two plays later, found fullback Darrel Young wide open in the end zone for a 20-yard touchdown that gave the Redskins (1-1) an early 7-0 lead they wouldn't relinquish.

Cousins, in emergency relief, finished the game completing 22-of-33 passes for 250 yards and two touchdowns in the Redskins' 41-10 blowout victory. Gruden confirmed Monday that Cousins will start on Sunday when the team opens up divisional play on the road against the Philadelphia Eagles, and is not yet thinking about what he could do down the road if Griffin III returns later this season while Cousins is performing well.

"We'll cross that bridge when that comes," the first-year head coach said. "Right now we're going to prepare with Kirk Cousins as our starter and Robert's going to rehab, and then all decisions after will come after that. But right now, we're going to go try to do the best we can, get Kirk ready to go and beat Philadelphia."

Gruden said the team has not ruled out bringing in another quarterback to place on the practice squad while Griffin III recovers from his injury. With Cousins being elevated to starter, third-stringer Colt McCoy – who was inactive the first two games – becomes the Redskins' backup quarterback.

Gruden, who earned his first win as an NFL head coach Sunday vs. the Jaguars, said the victory was bittersweet because he knows how hard Griffin III has worked all offseason to lead his team this year.

"You spend a lot of time with Robert getting him ready and you watch how much passion he has for the football game and how seriously he takes his job and what kind of will he has to succeed," Gruden said. "You spend a lot of time with Robert getting him ready and you watch how much passion he has for the football game and how seriously he takes his job and what kind of will he has to succeed."

Gruden said Sunday's injury is just another "bump in the road" for Griffin III, who has already recovered from major knee surgery in his two-plus years in the league.

"It's another little bit of adversity that he's going to have to overcome," Gruden said. "Part of being a quarterback is you mental toughness and ability to overcome adversity and he's done it in the past, he'll do it again, and we have total faith that he'll bounce back and be as good as ever soon."

Jackson Day-To-DayGruden said wide receiver DeSean Jackson is day-to-day with a shoulder strain also suffered in the first quarter of yesterday's game vs. the Jaguars.

According to Gruden, Jackson will test his shoulder this week in practice before the team is able to determine whether he can play Sunday in Philadelphia against his former team.

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