The Philadelphia Eagles throttled the Washington Redskins’ defense for the better part of three quarters, and the Redskins crippled themselves on offense with turnovers and penalties. But neither Coach Mike Shanahan nor his players saw any of the struggles as cause for concern following their 33-27 loss.

The Redskins entered the game believing they were well-prepared for what they would see out of the Eagles’ up-tempo offense, but the effectiveness with which the Eagles ran the attack caught the Redskins off-guard.

Unfamiliarity helped the Eagles to a large degree. As linebacker Brian Orakpo said, “This is something the NFL hasn’t really seen, what Chip Kelly’s doing. That’s all it is. We’ll be better next time we play them.” But at the same time, Orakpo and his teammates and head coach admitted that poor tackling and some blown assignments in the secondary proved more crippling than not having a complete feel for Philadelphia’s schemes.

Eagles running back LeSean McCoy had a 34-yard touchdown run on which he ran through a gaping hole, hurdled cornerback E.J. Biggers — who was pressed into safety duty with Brandon Meriweather still nursing a sore groin — and then raced untouched the rest of the way. Rookie free safety Bacarri Rambo missed an open-field tackle that would have prevented a 28-yard Brent Celek touchdown catch, and later whiffed on a shot at Michael Vick — a miss that led to a 36-yard scamper by the Eagles’ quarterback. Those weren’t the only botched tackles for the Redskins, who allowed the Eagles to convert seven of 15 third downs for first downs.

“We just need to learn from our mistakes,” Orakpo said.

“We’re not where we need to be, obviously. You know, 33 points,” cornerback DeAngelo Hall said. “I don’t even know where they were yardage-wise, but I remember coming in at halftime and seeing 320-something yards. That’s pretty frustrating. It’s kind of hard to win a football game like that. It’s one game, we’ve got 15 more. But when you’re wrong, you’re wrong, and we were definitely wrong about this team.”

The Redskins refused to blame a lack of preseason action and rust on Robert Griffin III’s part for their offensive struggles.

“You know, we stunk it up in the first half. We didn’t move the ball at all,” wide receiver Leonard Hankerson said. “We didn’t get any first downs, we didn’t score any points. The defense played pretty well, but with them being on the field as long as they were, they kept on getting tight. As an offense, we didn’t do our job and we let them down.

“We were just off,” Griffin said.

Three of the team’s most clutch players from last season — Griffin, Alfred Morris and Kai Forbath — all committed uncharacteristic gaffes. Griffin had two interceptions, the first of which saw him force a throw into triple coverage, Morris — who fumbled only four times last season — fumbled once and dropped a pitch for an Eagles safety. And Forbath, who made 17 straight field goals last season, missed his only attempt of the game.

But the Redskins on both sides of the ball drew encouragement from the second half, which saw them outscore the Eagles 20-7. Morris had a touchdown run, Griffin threw two touchdown passes, and the team had a chance to tie the game.

The Redskins players all vowed to play better next week, and to spend the week sharpening their skills, timing and discipline.

“You can’t change those expectations. They found a way to win the game, and we didn’t,” Shanahan said. “It’s a 16-round fight, and we lost the first round, and you just take them one at a time. But I was pleased with how we fought back. We did some things good in the second half, and you’ve got to keep on rolling.”