The Eagles (5-8), who finished the game with just one healthy running back, their third-team long snapper and three backups on the offensive line, finally succumbed when Ryan Kerrigan beat deep reserve right tackle Matt Tobin around the edge for a strip sack of Carson Wentz and a turnover to squelch a final Eagles' uprising.
Though the Eagles came from behind to take a fourth-quarter lead, key momentum was lost earlier — on a couple of third-quarter misplays that made a turned a potential 20-7 lead into a 14-13 deficit.
First, a 72-yard punt return for a touchdown by Darren Sproles was wiped off the board due to an illegal block penalty on Zach Ertz.
On Washington's ensuing series after forcing an Eagles punt, former Eagle DeSean Jackson beat cornerback Leodis McKelvin badly in one-on-one coverage down the field for an 80-yard touchdown that put Washington up 14-13.
The Eagles' problems were just beginning, too.
Hurting the their chance of coming back from that was a right wrist injury that forced long snapper Jon Dorenbos out of the game. His emergency replacement, Brent Celek, promptly botched the snap on a 50-yard field-goal attempt, forcing holder Donnie Jones to make a run for it.
He was stuffed for a big loss, setting up another Washington TD drive, which ended with a 15-yard pass from Kirk Cousins to Pierre Garcon.
Still, the Eagles responded in the fourth to briefly get the lead back.
McKelvin jumped a sideline route by Jackson, intercepted the pass and took it 29 yards for a touchdown to cut Washington's lead to 21-19.
Then, with Celek also knocked out of the game, third option Trey Burton's long snap was high on a field-goal attempt by Caleb Sturgis, but holder Donnie Jones was able to get it down in time for Sturgis to make good from 41 yards.
However, the Redskins bolted back into the lead for good when Chris Thompson scored from the Eagles' 25-yard line on a second-down play right after the 2-minute warning.
Wentz recovered from being intercepted in the end zone on a drive that could have given the Eagles a 10-point lead in the first quarter to rally the team from behind twice. He completed 32 of 46 passes for 314 yards and a touchdown."
"I thought Carson [had] probably his best game of the year, quite honestly, just the way he hung in there, battled the adversity with the changes up front," Eagles coach Doug Pederson said. "The guys worked hard for him, too. It was a great effort. We were down to one running back. I thought Ryan [Mathews] hung in there and did a good job as well. But Carson, overall, really did a nice job today."
Wentz targeted Ertz more times (13) than anyone else, leading to game highs of 10 receptions and 112 receiving yards for the player who came under fire for failing to block on a scramble out of bounds by Wentz a week earlier in Cincinnati.
Because the Eagles also were shorthanded at wide receiver due to an abdominal injury suffered by Dorial Green-Beckham the week before — he was deactivated as a result — Wentz leaned heavily on all three of his tight ends, who combined for 20 catches and 184 yards.
It might have been more had Celek not been injured.
"I think it sometimes just limits what [opponents] do a little bit," Wentz said. "I think some of it was Trey Burton and he can do a lot of different things for us. You saw that last week as well, he played quite a few snaps. I think that's just a combination of what they do and Trey has been a heck of a player as well."
Burton's versatility was never more evident than in this game.
"I was excited," Burton said. "I'm trying to take advantage of every opportunity I get and it went well. Donnie made an unbelievable play [to get the high snap placed perfectly]. The majority of it's on him and he did a really good job."
So did Jordan Matthews and (eight catches, 79 yards) and Mathews (15 carries, 60 yards) in his first action since being knocked out of a 26-15 loss at Seattle on Nov. 20.
Defensively, Fletcher Cox broke a long drought with 1.5 sacks, but the Eagles, aside from McKelvin's interception return, were mostly frustrated by Washington quarterback Kirk Cousins (14-for-21, 234 yards, two TDs, one interception) and an efficient running game that produced 107 yards.
Not nearly enough plays were made behind the line of scrimmage by the defense.
Though the loss didn't mathematically eliminate the Eagles from the playoffs, the reality is that their season will end on New Year's Day with a home rematch against Dallas.
The Eagles have an 0-4 record in their division.
"The main focus right now is to keep this team together and make sure everybody is on the same page," Cox said. "Everybody is still holding each other accountable. Everybody still believes in the coaching staff and what the coach is doing and trusting the way we prepare week in and week out.
"... We're professional athletes. They pay us to play this game and every guy in here knows that. They know that we're going to continue to do the things that we do. We're going to come out and practice and play hard and nothing is going to change. We are a team."
Added Pederson: "I told the guys at the end of the game here, 'Don't hang your head.' This is a great group. The guys hung together. They battled today all the way down to the end, really the last play of the game. It's great to be the head coach and to lead these guys and to see how far they've come. Through all the adversity throughout the season, they still hang together. As I mentioned during the week, you saw it today, I mean, there's no quit in these guys. The fight is there. That's a good thing to see."
Inactives: The Eagles began the game dangerously short at wide receiver and offensive line.
Because Dorial Green-Beckham, their second most productive wide receiver, still hadn't recovered from a devastating hit the week before, he was deactivated. Also scratched was starting right guard Brandon Brooks, who has an illness. Brooks also missed the Monday night game against Green Bay on Nov. 28 with a late-developing virus, but recovered in time to play last week at Cincinnati.
Brooks' absence meant the Eagles had to start rookie Isaac Seumalo at right guard. Left guard Allen Barbre, who was extremely overmatched filling in for the still-injured Hal Vaitai last week at right tackle, started the same spot again today, with Stefen Wisniewski starting at left guard.
The Eagles also deactivated running back Kenjon Barner to make room for having all six of their defensive ends active.
Other Eagles' scratches: LB Kamu Grugier-Hill, OL Dillon Gordon and DT Taylor Hart.