LANDOVER, Md. — The Philadephia Eagles’ defense continued to regress under new defensive coordinator Todd Bowles on Sunday.

Washington rookie quarterback Robert Griffin III threw four touchdown passes in a 31-6 Redskins victory at FedEx Field.

Since Bowles took over for Juan Castillo as defensive coordinator, the Eagles have allowed at least 28 points in their last four games. Under Castillo, they never surrendered more than 27 points and held three of their first six opponents to 17 or less.

“It seems like it’s been sloppy play for the last four weeks,” cornerback Nnamdi Asomugha said. “I feel like we haven’t been playing at the level we had been playing at. But I don’t think that has anything to do with the change in coordinators or the mentality of the defense. We are playing hard enough, but we’re missing tackles and missing assignments.”

There were two glaring breakdowns against the Redskins.

Fullback Darrel Young was all alone when he caught his 6-yard TD pass in the first quarter. Wide receiver Aldrick Robinson was even more wide open during his 49-yard TD reception in the second quarter.

“I wouldn’t say we’re getting worse,” defensive tackle Cullen Jenkins said. “But our performances are getting worse in some of these games. Every-body sees what we’re putting out there and it’s not good.”

McCoy gets concussion

Eagles running back LeSean McCoy followed quarterback Michael Vick as the second key player in as many games to suffer a concussion when he was hurt in the fourth quarter against the Redskins.

McCoy was shaken up when he was tackled by Redskins safeties Reed Doughty and Madieu Williams with 1minute, 45 seconds left in regulation and was eventually carted off the field.

McCoy appeared woozy and confused in the locker room after the game.

Eagles coach Andy Reid came under fire for even having McCoy in a game in which the Eagles had no chance of winning. They were behind 31-6 at the time.

“He was out there because we were trying to catch up and win the game,” Reid said.

Offensive line shakeup

Quarterback Nick Foles was not the only new starter on the Eagles’ offense Sunday.

Newcomer Jake Scott, who just signed with the team Monday, started at right guard ahead of Danny Watkins.

“When a team signs you on a Monday, they expect you to be ready to play on Sunday,” Scott said. “So I made sure I was ready.”

He split reps during the pregame warmups with Watkins, who had missed the previous three games with a chronic ankle soreness. He was listed as questionable on Friday’s injury report.

Scott committed two false-start penalties early in the game but also supplied a big block that helped spring McCoy for a 25-yard gain on a screen pass.

Scott was playing for the first time this season after spending eight seasons with Indianapolis and Tennessee. Eagles offensive line coach Howard Mudd was his line coach with the Colts.

Out of action

In addition to Vick, wide receiver Jason Avant was deactivated with a strained hamstring. He missed a game for the first time since 2008. Other inactives: defensive end Vinny Curry, wide receiver Mardy Gilyard, defensive end Phillip Hunt, guard Nate Menkin and running back Chris Polk.

Up ahead

The Eagles (3-7) return to Lincoln Financial Field to face Carolina (2-8) for the first time since 2009 next Monday night. The Eagles hold a 5-2 advantage in the series and have won three straight over the Panthers. In their most recent meeting, the Eagles opened the 2009 season with a 38-10 win at Carolina. The Panthers are playing in Philadelphia for the first time since 2006.

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