Redskins quarterback Colt McCoy slowly walks toward the locker room after suffering a season-ending injury in Monday night's loss to the Eagles. (Jonathan Newton / The Washington Post)

PHILADELPHIA — The Washington Redskins lost their second starting quarterback for the season Monday night when Colt McCoy went down with a leg injury in the second quarter of the team’s 28-13 loss to the Philadelphia Eagles. Coach Jay Gruden confirmed after the game that McCoy suffered a fractured right fibula, which will keep him out the rest of the year.

“This is a tough blow,” Gruden said. “Losing Alex [Smith] is one thing, a great leader, great quarterback. Put in a lot of time with him. Colt finally gets his golden opportunity and he gets kicked in the leg and breaks it. Heartbroken for both of those guys, really . . . Those two guys are two tough-minded, tough people. Great competitors. If I had my money down, I’d imagine they’ll both be back somehow, some way.”

McCoy was sacked on the last play of the first quarter by Malcolm Jenkins and appeared to have his right ankle twisted at an unnatural angle around Jenkins' leg. The quarterback went down after scrambling from pressure, but spun onto his stomach as he hit the ground. That motion whipped the outside of McCoy’s right leg against Jenkins' planted left knee.

McCoy came back and played the final two snaps of the series, which came at the start of the second quarter, before Dustin Hopkins kicked a 44-yard field goal. He was then seen limping along the sideline as backup Mark Sanchez, who was signed Nov. 19 after Smith broke his leg, warmed up. Smith is out for the season after breaking both his right fibula and tibia against the Houston Texans.

As McCoy went to the locker room, Sanchez came in with the Redskins starting on their own 10-yard line. Running back Adrian Peterson broke loose for a 90-yard touchdown on Sanchez’s first snap since Jan. 1, 2017, when he played for the Cowboys in Philadelphia. Sanchez was a backup for the Chicago Bears last season, but didn’t play a single snap. He completed 13 of 21 passes Monday for 100 yards with no touchdowns and one interception. Gruden said Sanchez wore a wristband with numbered plays to try to help in case of emergency, with the week of practice spent preparing McCoy.

“It was a tall task, no doubt,” Sanchez said. “But there’s no excuses to make. You just do your very best. I’m grateful for the opportunity. I was praying for an opportunity and I thank God for an opportunity. You just never want it under these circumstances. So with respect to Alex and Colt, I’ve got to do my very best to play well and help rally this team and figure out a way to win.”

The team will have to sign another quarterback just to get through the end of the season, and decide if it wants to commit to Sanchez as the starter or open up competition with whomever is added to the roster.

The Redskins felt confident moving forward with McCoy as the starter, in part because he’s a favorite of Gruden’s and has been in the system since 2014. There was no need to start from scratch, and the team felt he would fare much better with the extra practice time between the Redskins' Thanksgiving game against the Dallas Cowboys — in which McCoy threw for 268 yards with two touchdowns and three interceptions in a 31-23 loss — and Monday night’s contest. But he only lasted one quarter, completing 4 of 4 passes for 50 yards.

It’s uncertain whether either Smith or McCoy will be ready for organized team activities in the summer.

“It’s tough to see one of the good guys get hurt,” linebacker Mason Foster said. “Being in my eighth year and seeing how easily people can get hurt and ends their year, I think Colt’s Year 9 and Alex [Year 14], it’s tough . . . It’s crazy because they’re your friends, they’re your brothers . . . it’s so crazy how quickly your season could be done. It sucks, man, to see them get hurt like that.”

The Redskins declined to carry a third quarterback on their 53-man roster this year, releasing third-stringer Kevin Hogan at the end of preseason. Hogan signed with the Denver Broncos after his release from Washington.

Washington held a workout of free agent quarterbacks on Nov. 19, the day after Smith broke his leg against the Texans. The group included Sanchez, E.J. Manuel, T.J. Yates, Kellen Clemens and Josh Johnson. The Redskins mentioned Sanchez’s familiarity with some members of the Redskins' coaching staff, including offensive coordinator Matt Cavanaugh, as a contributing factor to his selection. Sanchez was a four-year starter for the Jets after being selected with the fifth overall pick in 2009.

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