The Post Sports Live crew dissect the Redskins performance in the loss to the Eagles on Monday night. (Post Sports Live/The Washington Post)

The Washington Redskins kicked off their season against the Philadelphia Eagles at FedEx Field on Monday night. But the much-heralded return of Robert Griffin III and the defending NFC East champions fell short of the expectations players, coaches and their fans had.

The second-year quarterback battled rust for the better part of three quarters and his defense struggled in vain to slow the tempo of new EaglesCoach Chip Kelly’s highly touted spread offense. The end result was a 33-27 loss in a game that for the most part was a rather lopsided affair.

Griffin, who played in his first game since tearing his anterior cruciate ligament on Jan. 6, and the Redskins’ offense turned the ball over three times – twice in the first two possessions — and didn’t score a point until less than two minutes remained in the third quarter.

“I think that’s an excuse,” Griffin said when the idea of rustiness was raised postgame. “I’m responsible for the way I play. I didn’t play very well in the first half. That’s just the way it is. You move on from it. I’m not going to sit here and say I was rusty. I’ve got to be accountable and I’m going to be accountable for that. I didn’t play well in the first half. We came back and played better in the second half. We’ve just got to do it for 60 minutes.”

Meanwhile, the defense — despite scoring a first-quarter touchdown off of a fumble recovery — couldn’t offer the support that the offense needed, and gave up 322 yards and 26 points on 43 plays in the first half.

By the time the offense got going, the deficit proved too significant to overcome, and Washington suffered its first Week 1 loss under Mike Shanahan since he took over as coach in 2010.

Shanahan couldn’t pin the blame on any one player.

“It’s everybody. It’s not just one guy, until I look at the film. You’ve got to have 11 guys going together. You have nine, 10, sometimes it looks the way it did. You just can’t get any momentum and you turn the ball over early, put our defense in some tough situations and we just couldn’t catch up.”

“Had a serious case of the ‘can’t get rights,’ Griffin said. “Just penalties, hurting ourselves. I don’t throw picks, Alfred [Morris] doesn’t fumble and Kai [Forbath] doesn’t miss kicks and all three of those things happened tonight.”

Griffin finished the game 30 of 49 for a career-high 329 yards, two touchdowns and two interceptions, with both touchdown catches by wide receiver Leonard Hankerson, and 169 of those passing yards coming in the fourth quarter.

Meanwhile, Philadelphia running back LeSean McCoy rushed for 184 yards and a touchdown on 31 carries as his Eagles outgained the Redskins 445-382 in front of a crowd announced at 82,743.

The Eagles shot out of the gates at a blistering pace, going 76 yards in nine plays, moving from the Philadelphia 20-yard line to the Washington 4 using a no-huddle attack that made it hard for Washington’s defenders to get a read on what their opponents were doing. Then the Redskins capitalized on a bizarre play that resulted in a defensive touchdown.

On first and goal, Vick took the snap and scanned the end zone for an open receiver. A wide gap in the defense presented itself, but the quarterback either didn’t see it, or didn’t want to run. He turned instead to his right and threw a pass to McCoy behind the line of scrimmage. Redskins linebacker Ryan Kerrigan batted the ball backward, and it bounced to the 25-yard line, where cornerback DeAngelo Hall scooped it up and returned it uncontested 75 yards into the end zone.

The play was reviewed to see if the Vick’s throw had been a forward pass or lateral, and the officials let the score stand. It marked the fourth consecutive home opener in which the Redskins have scored a defensive touchdown. Two (both fumble recoveries) belong to Hall, and Kerrigan and Rob Jackson both scored on interceptions.

But the Eagles got right back to work, moving the ball 51 yards in nine plays before having to settle for a 48-yard field goal.

By the time Washington’s offense took the field for the first time, the Eagles had already run 19 plays and racked up 121 yards.

The Redskins’ offense — which ranked fifth in the NFL in 2012 — didn’t get off to a strong start, however, as Morris took a shotgun handoff, gained three yards and fumbled.

Philadelphia recovered at the 25 and needed one play to score. Vick connected with DeSean Jackson, who had a cushion between he and Hall and made the easy catch in the back of the end zone.

On the next possession, Griffin threw his first pass — an eight-yard toss to Fred Davis. But a penalty negated that play. Griffin then completed a screen pass that Morris turned into a nine-yard gain, and on third and nine, Griffin took to the air again — but he probably wished he hadn’t. With no open receivers, Griffin tried to force the ball to Santana Moss down the center of the field. But Moss was bracketed by defenders, and Eagles cornerback Brandon Boykin, who had underneath coverage, intercepted the pass in stride, giving Washington its second turnover in four plays.

And things didn’t get any better offensively. The defense forced the Eagles to punt after four plays, but on second and 10 from the Washington 5-yard line, the Redskins committed another blunder. Morris couldn’t secure a pitch from Griffin in the end zone and had to fall on the ball for a safety.

By the time the first quarter ended, the Eagles had run 29 plays to the Redskins’ nine, and had outgained Washington, 202-30, despite holding only a 12-7 lead.

The slim margin didn’t last long, however. Vick completed a 28-yard touchdown pass to Brent Celek to give his team a 19-7 lead with 6:10 left in the quarter, and then the quarterback scored on a three-yard draw that gave Philadelphia a 26-7 lead with 58 seconds left before the half.

Griffin threw another interception on Washington’s first possession of the third quarter. as cornerback Cary Williams made a leaping catch to snatch the ball from the air just before it reached Pierre Garcon’s hands on an out route. (It marked the first multiple-interception game of Griffin’s young career. He threw only five interceptions all of last season).

Two plays later, McCoy took the handoff, made defensive back E.J. Biggers miss, sent safety Bacarri Rambo sprawling and raced the rest of the way unchallenged for a 34-yard touchdown.

Griffin and the Redskins’ offense finally seemed to settle into a rhythm midway through the third quarter. Griffin completed 4 of 5 passes on a 55-yard drive that stalled at the Philadelphia 22. But Forbath missed a 40-yard field goal attempt, extending Washington’s scoring drought.

Washington finally put it together on its final possession of the third quarter. Griffin completed 5 of 7 passes on an eight-play, 66-yard drive capped by a five-yard touchdown run by Morris.

The Redskins’ defense forced another turnover when Josh Wilson jarred the ball free from wide receiver Jason Avant’s grasp, and linebacker Perry Riley Jr. recovered at the Philadelphia 29.

That gave Griffin and company a short field to work with, and the quarterback completed a 10-yard touchdown strike to Hankerson. The two-point conversion pass attempt fell short, and the score stood at 33-20. The Redskins had two more offensive possessions down the stretch, but had to punt on the first. Hankerson caught a 24-yard touchdown pass with less than two minutes left. But Washington failed to recover an onside kick, and Philadelphia escaped with the victory.