When the Eagles went inside after warm-ups, approximately one hour before kickoff, there was a fresh coating of snow on Lincoln Financial Field's grass turf. The precipitation was light and the visibility was fair.
But the weather turned from "School is on, the buses can drive," to "School is off, time to go sledding." The snow picked up at a pace to which the stadium grounds crew couldn't keep up in their efforts to clear the yard markers and sidelines.
So when the Eagles left the warm confines of their locker room and walked back out of the tunnel, the Linc had turned into a winter wonderland, and the Lions, in white, blended into the scenery.
"I know when I turned the corner," Eagles coach Chip Kelly said, "I was like, 'Oh, this is interesting.' "
Kelly is from the northeast, coached in New Hampshire for years, but he said he had never played in a game with as much snow. Some of the players said the same. Many had never played in snowy conditions.
For most of the first half, it looked like the Detroit Eskimos were playing the Philadelphia Surfers. The Surfers, er, Eagles had minus-1 yard to the Lions' 144 yards at one point in the second quarter.
But Kelly and the Eagles somehow, unfathomably, as the snow slowed in the second half, hit the gas after being stuck in neutral and scored 34 points and gained 367 yards in the final quarter and a half.
And the secret to the turnaround - aside, of course, from the obvious talent of LeSean McCoy - was Kelly's bread-and-butter play. The Eagles coach kept calling for the inside zone, and the offensive line and McCoy kept opening holes and running through them on the way to a 34-20 comeback for the (ice) ages.
"One of the easiest plays for us to run, something we do every game, is the inside zone," center Jason Kelce said. "And when we were doing it in the game we were getting good yards on it. I just didn't really expect us to get that explosive with it."
The Eagles had mild success with the inside zone - a run play designed to go up the middle that often involves combination blocking - late in the first half. But Kelly came out throwing in the second half.
There was a method to his madness, though. He knew he needed quarterback Nick Foles to complete a few downfield passes to force the Lions' back seven on its heels. And Kelly thought he knew what kind of routes would break his receivers free after Eagles cornerback Cary Williams offered a suggestion.
"He was like, 'Coach, this is what you've got to do, because you can't make up speed if the guy makes a stick move on you because of the footing,' " Kelly said.
So after the Lions went ahead by 14-0, Kelly called for a play that had receiver Riley Cooper running a post. Foles' throw was on target, but a Lions defender had good coverage. Cooper, though, made a diving grab for 44 yards.
"It's crazy Coach went along with me," Williams said. "It's weird because you don't get a defensive player telling a head coach, 'Hey, this is a great possibility if we run this particular route.' "
Foles hooked up with DeSean Jackson for a 19-yard touchdown pass a play later, and the Eagles were finally on the board. On their next possession, Foles completed only one of his next four pass attempts - a 25-yard throw to Cooper - but something cracked.
The offensive line started to dominate against the league's No. 2-ranked run defense. Guard Evan Mathis credited a halftime cleat change. But none of the other linemen changed his gear. They did say they altered their footing, though.
"I think the bigger part of that was not getting overextended with your steps, keeping your feet under you," Kelce said. "When I started doing that, I started having a lot more success."
Kelce, Mathis, and right guard Todd Herremans were opening holes at the point of attack, mostly against defensive tackles Ndamukong Suh and Nick Fairley, no less. And McCoy was making second-level defenders miss with his ankle-breaking moves.
He ran 40 yards for a touchdown, and then 57 yards for another score and then 26 yards on the first play of a drive that ultimately netted another six points. All told, McCoy ran 29 times for an Eagles-record 217 yards.
"I think everybody was so intimidated and scared of Detroit's guys up front, but I thought the big guys on my team took the challenge and stepped up," McCoy said. "The whole week they talked about just running the ball and giving me different matchups one-on-one."
With McCoy's cutting ability, he was able to slice through holes on the back side. Kelly credited tight end Brent Celek's blocking. In the first four games of the Eagles' five-game winning streak, they won on offense mostly behind the strength of Foles and the passing game.
McCoy was excellent in Green Bay, and he was more than adequate in the other games. But defenses have been intent on slowing him and asking Foles to beat them (which he has) through the air.
But Kelly is a masterful play-caller in the run, and Sunday was the best the Eagles have looked on the ground since September. There's been some hand-wringing about the run game being less effective with Foles rather than Michael Vick under center.
But it sure didn't look that way once the snow lightened and you could see.