Nick Foles doesn't want to dwell on what went wrong for him against the Cowboys on October 20th, nor should he. Sure, he should watch some tape with the coaches and look for things to fix. Otherwise, just focus on executing now. "If I look into every little thing that I did and try to break it down, I'll drive myself crazy as well... everyone wants an answer, but I think the answer is that we had a bad day."

That's great for him, but those of us who aren't performing on the field Sunday want to know what happened. Most people have accepted that Foles is the Eagles' quarterback of the future, but we'd be a lot more comfortable if we had some (hopefully temporary or one-off) reason for that failure.

You probably know the numbers -- 11 of 29 for 80 yards and a 46.2 passer rating -- but even they don't express how poorly Foles led the Birds on that day. He got only 10 first downs all game, and two of those were on penalties. Here's how Foles' drives ended: Donnie Jones punted 9 times and Alex Henery missed a desperation 60 yard field goal. The Eagles' only 3 points came after Demeco Ryan's interception and runback, when they were able to start from the Dallas 30 yard line. Nick only got the Birds down to the Dallas 9 yard line before he was literally knocked out of the game, after holding the ball for more than 9 seconds on a third down pass play. Miserable.

What did it look like? There were some drops, and Shady had a poor day too, and Bryce Brown fell down untouched, but mostly Foles just missed wide open receivers with bad throws -- at least nine, including Jason Avant as wide open in the end zone as anyone ever is. So what caused Nick to look so bad in the middle of an outstanding year?

Here are some leading theories:

1) Pressure. Even though it was only game 7, this was a duel with the hated Cowboys for first place in the division. Vick had been starting after winning the QB competition solidly in training camp, so Nick had two reasons to feel pressure to perform. However, he had started six games under dire circumstances in his rookie year, and has shown no sign of folding under pressure since. So if that was the cause, good news -- he seems to have solved the problem.

2) Concussion. I can't find the source, but after that Dallas game at least one person thought they saw Nick take a hard shot to the head early in the game, and suggested that he was possibly dazed or foggy the rest of the way. Alternately, Foles might have just felt the pressure of a strong rush early and gotten jumpy for the rest of the game.

Foles is known for playing tough

On the second play from scrimmage, Foles was sacked by George Selvie, and two plays later he was knocked down by Bruce Carter (with an intentional grounding call). The Selvie hit didn't look bad, but Carter's tackle may have snapped Foles' head against the turf, just like the third quarter sack that knocked him unconscious. (None of the camera angles give a clear enough view to be sure; the photo above is a screen shot.)

Foles is known for playing tough; Chip Kelly has admired him for years for precisely this reason. It's certainly conceivable that he didn't want to surrender his chance to take the helm in Philadelphia (especially with Vick already out injured) and decided to try to play through his grogginess. That would also explain why he couldn't 'fess up to it later.

This is another "good" answer in that Foles has obviously played well since, so any concussive effect has been dealt with. The only down side is that two concussions in a day will cause significantly more damage than one, much more than simply doubling the effect. Foles had a concussion in college as well, and there are only so many hard shots a brain can take before a player needs to stop playing. But for now, all appears well.

3) Spy for Texas. Nick Foles grew up in Texas, played high school ball in Texas, and still has family there today. The Eagles have played Dallas 3 times since Foles was drafted, and lost each game. The first time, on Armistice Day 2012, was the game where Michael Vick was injured and Foles took over. So is Foles throwing these games? Did he send a secret "injure Vick" signal to his home state colleagues, and harness UFO's tractor beams to redirect his own passes into the turf? We'll discuss all of these theories on the next episode of Alex Jones' All-Conspiracy Radio.

None of these causes are likely to repeat

In the end, the most likely explanation seems to be a combination of early hard hits and solid defense all game by the Cowboys. Yes, I realize that "solid defense by the Cowboys" is even stranger than "bad passing by Nick Foles," but it actually happened -- we have the tape to prove it. Dallas rushed hard (even without DeMarcus Ware) and played tough man-to-man coverage against the Eagles. This was also before the offensive line solidified and the Eagles' coaches devised some of their strategies for punishing man coverage.

Maybe Foles was playing through a brain fog, or maybe the early hits just gave him happy feet in combination with continued strong pass rushing, big game yips and the pressure of his quarterback competition.

The important thing is, none of these causes are likely to repeat. Unless Nick is a no-good, rotten, two-faced Texas spy. But I'm willing to take that chance.