Even before officials had ruled that C.J.?Mosley fumbled his interception return just a couple of feet before crossing the goal line in the third quarter of the Ravens' 16-10 loss to the Washington Redskins at M&T Bank Stadium on Sunday, the inside linebacker knew the mistake he had made.

Even worse, his error was compounded by a hamstring injury he suffered as he attempted to dive for the pylon in the front left corner of the end zone.

“I knew immediately,” Mosley said. “So on top of the hamstring and then that, that was a tough one, a tough break.”

The play proved critical. Instead of the Ravens taking a 16-13 lead with 6:09 left in the quarter, the touchback returned possession to Washington, which began the ensuing series at the 20-yard line. Eleven plays and 72 yards later, Dustin Hopkins converted a 27-yard field goal to give the Redskins a 16-10 advantage that would hold for the rest of the game.

Mosley had made a sensational play on his team-leading third interception of the season. Reading quarterback Kirk Cousins' eyes on second-and-8 from Washington's 3, Mosley dropped back and leaped to snare Cousins' pass to tight end Jordan Reed on a quick slant.

Mosley wove his way 12 yards, but with less than a yard left before scoring what would have been his first career touchdown, he lost control of the ball.

“Two hands on the ball. That's all I can say,” said Mosley, who will undergo an MRI on his hamstring today. “Tried to make a good play, and it ended up backfiring. So if I ever get the chance again, I know not to dive with one hand.”

Coach John Harbaugh did not fault Mosley's effort but rued the execution.

“You have to hold on to the ball there,” he said. “Take two hands over the top of the pylon — that would be a technique coaching point. Other guys do it with one hand and hold on to the football. That's a very costly [play]. Not only do you lose the turnover, you lose 19 yards of field position. I think it's a crazy rule, but we have to understand that, and you have to protect the football when you're doing that.”

Injury list grows: In addition to Mosley, the Ravens lost wide receiver Steve Smith Sr., right tackle Rick Wagner and cornerback Sheldon Price to injuries Sunday. None of those four players returned to the game. Wide receiver Mike Wallace got hurt on the offense's final attempt to tie the score.

Smith, who left after catching a 7-yard pass in the first quarter, told a group of reporters that he rolled his ankle and was not talking.

Asked how the ankle felt, Smith replied, “How does it feel? It feels like [expletive].”

Wagner is battling a thigh ailment suffered in the second quarter. “We don't know too much,” he said. “I only saw the doctor for, like, two minutes. We'll do some tests tomorrow and have a better idea.”

Price, starting for Shareece Wright, who was deactivated after battling what team officials described as back spasms, injured his left hamstring in the first quarter. His thigh was heavily taped after the game.

Wallace absorbed a shot to his ribs from Washington inside linebacker Will Compton while trying to catch a pass from quarterback Joe Flacco on fourth-and-8 from the Ravens 21.

“I wanted to bounce up fast, but that one kind of got me,” Wallace said. “I think that is the longest I have ever been down in my career.”

Young gets extended playing time: With Wright inactive and Price injured, the defense turned to rookie Tavon Young, who joined starter Jimmy Smith in covering Redskins receivers on the outside.

“All week, Coach told me that I was the next man up, so I was ready,” said Young, the first of the club's five picks in the fourth round of the 2016 NFL draft. “Once my moment came, I just went out there and played with confidence. I just did what I know.”

Harbaugh took note of Young's performance, which included three tackles. “Tavon has played well,” Harbaugh said. “I think Tavon's had a really good season as a rookie. He's played five good games for us, whether we put him inside or in the slot.”

Lewis gets start at left tackle: Rookie Alex Lewis made his first start at left tackle since graduating from Nebraska for the injured Ronnie Stanley (foot), and acquitted himself well.

Also a fourth-round pick in the draft, Lewis did not allow a sack or commit a penalty Sunday, but said there was room for improvement.

“It's like being on a bike again, but I've got to be consistent,” said Lewis, who started the first three games at left guard. “I've got to be more consistent out on the edge there, and we've got to keep Joe upright.”

John Urschel, who started at left guard, surrendered a sack to Washington defensive end Ziggy Hood in the second quarter but was not flagged for a penalty.

End zone: Redskins inside linebacker Terence Garvin, a Baltimore native who played at Loyola Blakefield, made two tackles and shared a sack of Flacco in the third quarter with outside linebacker Trent Murphy. … In addition to Stanley and Wright, the Ravens deactivated rookie inside linebacker Kamalei Correa, rookie defensive tackle Willie Henry, safety Marqueston Huff, rookie outside linebacker Matthew Judon and rookie wide receiver Chris Moore. It marked the first time Correa and Moore have been healthy scratches in their careers. … Running back Justin Forsett, who was released by the Ravens on Tuesday, will meet and work out with the Detroit Lions today. Forsett, who averaged 3.2 yards per carry while starting in the first three games, could fortify a backfield that lost Ameer Abdullah (foot) for an extended time, and has been using Theo Riddick. … Washington deactivated cornerbacks Bashaud Breeland (strained tendon in ankle) and Dashaun Phillips (hamstring), rookie inside linebacker Su'a Cravens (concussion), rookie wide receiver Josh Doctson (Achilles tendon), rookie defensive end Anthony Lanier, right tackle Vinston Painter and rookie quarterback Nate Sudfeld. … Baltimore native and 23-time Olympic gold medal swimmer Michael Phelps led the offense out of the tunnel before the game. Former Ravens inside linebacker Ray Lewis and wide receiver Derrick Mason also attended the game. … Defensive end Lawrence Guy, fullback Kyle Juszczyk and tight end Dennis Pitta represented the Ravens for the coin toss.

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