For 30 minutes and two quarters of football, Chip Kelly's NFL debut seemed like a dream. The offense was run at a higher pace than has ever been seen at the NFL level, and it was working.
The Eagles marched down almost effortlessly at times, running the offense like a beautifully conducted symphony, on route to a 33-7 lead by the third quarter.
Yet, from then on, things spiraled downhill—fast. After looking like the vastly superior team for two-and-a-half quarters, the Eagles allowed 20 unanswered points from the Redskins and barely escaped with a win.
With a 26-point lead, a lot of the blame has got to fall on the defense.
But there were other factors that contributed to Washington's late-game rally.
For instance, the Eagles offense failed to score a touchdown since McCoy's 34-yard TD run with 13 minutes and 35 seconds left in the third quarter. That left Robert Griffin III, one of the most talented quarterbacks in the league, with nearly two whole quarters to mount a comeback. That's plenty of time when he is facing one of the less talented defenses in the NFL.
Still, a 26-point lead is usually very easy to defend. But the Eagles, after showing blinding speed for the first half of the game, looked completely gassed in the second half.
Signs of fatigue in the second half were everywhere.
Vick looked slower and less energetic when dropping under center compared to the first half. The offensive line began committing mistakes and losing focus. Even McCoy had to be taken out of the game at one point to catch his breath.
In the postgame press conference, Vick admitted that his first game in a Chip Kelly offense was a workout, stating that it was something he had never experienced before in his life.
"When the first quarter ended, I felt like we were going into halftime," he said with a laugh. "It was unreal."
It's very likely that the high tempo of the first half left the Eagles offense without much energy for the second half, leading to more third-and-outs, and therefore giving the opponent plenty of time to play catch-up. In this case, the Redskins very nearly caught up, were it not for a one-handed on-sides kick recovery by Jason Avant.
However, concerns about the sustainability of Kelly's offense are not just limited to physical limitations of players. Vick suffered a lot of hits last night. Punishment of the quarterback is more likely in Kelly's offense due to more designed running plays for the quarterback.
Vick's physical talent makes him the perfect fit for Kelly's offense and is likely what won him the starting quarterback job, but can he remain healthy playing in it?
In the press conference, Vick admitted he took a lot of hits in yesterday's game.
"I didn't put myself in position to protect myself at times."
Furthermore, Kelly's offense, while designed to catch defenses off guard with its fast tempo, can seemingly be thwarted with NFL loopholes. More and more reports have arisen lately of suspected faked injuries in an effort to slow the opposing team's momentum.
DeSean Jackson stated in his postgame press conference that he believed players were "going down with injuries to slow [the Eagles offense] down." If that's true, defensive coordinators may already be taking away one of the Eagles offense's biggest strengths.
Kelly's offense is based largely upon catching the defense out of position, which is why plays are run so quickly. But if an "injury" can give the coaching staff time to evaluate and substitute personnel, can Kelly's offense continue to be as successful?
This was a great win by the Eagles, but there is still plenty of uncertainty to go around. Can the players physically run such a high-tempo attack week in and week out? Can an injury-prone mobile quarterback remain healthy in this system? Can this system survive the weekly dissection by NFL defensive coordinators, game planning how to stop it?
Only time will tell, but one thing is for sure.
While this offense is designed to make scoring easy, running it consistently and effectively will be anything but easy for the players involved.
At the end of the press conference, Vick bemoaned the strain Kelly's offense put on his body.
"It's going to be a long season."
If Vick is tired now, imagine how he's going to feel around Week 8.
Follow Yueh Ho on Twitter @YuehHo