It was the loss that really sent the Eagles into a downward losing spiral.
They were 4-2 going into Dallas late last October, they were up 10 points early in the fourth quarter and up a touchdown and within field goal range with 7½ minutes left in the fourth quarter.
And still, they lost.
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Before you knew it, 4-3 turned into 5-9. By the time the Eagles beat the Cowboys on the last day of the season at the Linc, the Cowboys were on the way to the playoffs and resting their starters, and the Eagles were playing out the string.
On Wednesday, with the Eagles a few days from a greatly-anticipated rematch with the Cowboys, head coach Doug Pederson spoke about how much he learned from that devastating loss to the Eagles' biggest rival 13 months ago.
"What did I learn? No. 1, you hate to lose any week," Pederson said. "The other thing is just we had opportunities in that game to make some plays and change the outcome of that game. And I learned from the decisions I made in that game, and I've corrected those this season from the preseason on.
"And those are some of the takeaways. And for us as a football team, we're learning how to finish those games now this season. And that's a tribute to the players in the locker room."
The Eagles go back to Dallas this weekend with a much better team and a much better coach.
The Eagles are 8-1 with a seven-game winning streak going into their nationally televised NFC East showdown against the Cowboys at AT&T Stadium in Arlington, Texas. The Cowboys are 5-4 but 2-0 in the NFC East.
The Eagles have won five of their last seven games in North Texas. But last year was rough.
The Eagles just gave it away.
They led 20-10 late in the third quarter and were one score from putting the game away when the Cowboys ran a fake punt on a 4th-and-8 from their own 27-yard line. Punter Chris Jones ran 30 yards for a first down - the Cowboys' longest run against the Eagles in seven years. That led to a field goal and made it a one-possession game.
With eight minutes left in the fourth quarter, the Eagles still led by a touchdown and had a 3rd-and-8 on the Dallas 30-yard line. But an ill-fated play - a Carson Wentz backward pass to Darren Sproles - lost six yards, knocking the Eagles out of field-goal range.
Donnie Jones punted down to the 10, but the Cowboys drove 90 yards for the game-tying touchdown, then won in overtime on Dak Prescott's TD pass to Dez Bryant.
"They had the fake punt, got us last year," he said. "They marched the length of the field and scored. And we had opportunities in that game. That's what I said earlier about us learning how to finish those games and putting those teams away.
"We weren't able to do that last year and make those plays and offensively stay on the field and defensively get off the field. And that was definitely one we looked at a year ago. And it did slip away because you had the lead there early in the fourth quarter."
Pederson said the sequence late in the fourth quarter that knocked the Eagles out of field goal range also haunted him after last season.
"(We) had a chance to maybe kick a field goal and I have to do a better job at coaching the actual play," he said.
"It was a third-down situation, and I've got to do a better job at the teaching of the play. It starts with me. And we didn't execute the play very well. And it knocked us out of potential field goal range and it would have extended our lead at that time.
"So (I learned from) just those types of decisions where maybe you do something a little bit differently, call a different play or, in that case, just teach that play at that time better."