"He is the best quarterback in the NFL," Eagles coach Andy Reid praised his guy. "I don't think I have to say anything more than that."
Manning, meanwhile, never resembled the poised quarterback who won last year's Super Bowl MVP award with that one perfect spiral to Plaxico Burress.
Five times New York got inside the Eagles 20. The result? A mere three field goals.
"When we needed to get something done, get a spark to make a big play, that's when we didn't do our best," Manning said.
Credit Philadelphia's hard-hitting, ball-hawking defense, and maybe blame the wind gusts a bit. Either way, these NFL playoffs are now for the Birds - the underdog Eagles, Cardinals and Ravens all won on the road this weekend.
McNabb lunged for one touchdown, threw for another and converted several key third downs to move the sixth-seeded Eagles (11-6-1) into next Sunday's title game at Arizona (11-7). Philadelphia beat the Cardinals 48-20 on Thanksgiving night.
David Akers added three field goals - extending his NFL record to 18 straight in the postseason - to fend off the top-seeded Giants (12-5).
"I am very, very disappointed," Giants coach Tom Coughlin said. "I am sorry to see the season come to an end. There is remorse for opportunities lost."
The swirling winds played havoc with any ball in the air, and also helped skew the score: This was the first game in NFL history to finish 23-11, the Elias Sports Bureau said.
A year after road success fueled the Giants' route, the Eagles are taking the same path. They opened the postseason by winning at Minnesota and, after their sixth victory in seven tries, look nothing like a team that needed several breaks on the final day simply to make the playoffs.
Benched by Reid in late November for half a game, McNabb never has acknowledged that the slight hurt him. He has, however, seemed to play with a huge chip on his shoulder, to the Eagles' benefit.
McNabb converted a third-and-20 set up Akers' 34-yard kick for a 13-11 lead in the third quarter. On the first play of the fourth quarter, he made a perfect play-action fake for a 1-yard TD toss to Brent Celek.
"The players executed like crazy," Reid said. "They never wavered one bit. That's tough to find in this league."
Manning was in trouble from the start. His first pass wobbled out of his hand, got caught in the wind and missed a wide-open receiver.
Manning ended up 15-for-29 with two interceptions, often overthrowing his targets. The Giants did not score a touchdown and lost for the fourth time in five games.
"It all comes down to what you do in the playoffs. That makes your season a good one or a disappointment," Manning said. "This is a disappointment.
"We felt this was a special team that could go far. The defense played outstanding today and gave us opportunities. Offensively, we didn't do our job. We didn't score enough points."
By the final two minutes, more than half the crowd had left; Big Blue hasn't won a playoff game at Giants Stadium since 2000. Philly fans headed down the New Jersey Turnpike after another big win for their city - the Phillies won the World Series in October.
"In the locker room, there was so much energy in there. We were ready to play early in the week," McNabb said. "The city of Philadelphia is buzzing; this team is buzzing."
Three road teams won on the same weekend in the NFL playoffs for the first time since 1971. Also for the first time, none of the top three seeds in NFC made it to the conference championship.
With Arizona and Philadelphia advancing, it guaranteed the NFC will send a team with no more than nine wins in a full, regular season to the Super Bowl for the first time since the Los Angeles Rams in 1979. Those Rams lost to the Steelers.
The Eagles won for the second time this season at the Meadowlands, and were the only team to win on Giants' turf.
"Last year we were the road warriors. This year, I thought we would be the warriors at home. It just didn't come to pass," Coughlin said.
Overall, McNabb's stats were not overwhelming: 22-for-40 for 217 yards and two touchdowns. He also got called for intentional grounding in the end zone for a safety.
Yet on a day where the conditions weren't ideal, McNabb kept his composure.
Once Ahmad Bradshaw returned the opening kickoff 65 yards, little went right for the Giants. John Carney missed two of five field-goal tries, New York missed open-field tackles and the team did not demonstrate last season's resolve.
Then again, Coughlin's team has changed: Michael Strahan retired, Osi Umenyiora and Super Bowl hero David Tyree were injured, and Burress was suspended after accidentally shooting himself in the thigh. New York went 1-4 since that banishment.
Moments after Manning missed his first throw, he made a much more costly pass.
Flushed from the pocket deep in his territory, Manning slung a pass that badly sailed - right into the hands of cornerback Asante Samuel. It was Samuel's seventh career postseason pick, and he brought it back to the 2.
McNabb made it count, stretching the ball over the goal line on a sneak for a 7-3 lead.
Unable to sack McNabb in two games this season, the Giants did even better early in the second quarter. The elusive QB dropped into his end zone and, facing pressure from the front and Justin Tuck's rush from the back, McNabb simply got rid of the ball into open space.
A penalty flag flew a split-second later and McNabb was called for intentional grounding, resulting in a safety that cut Philly's lead to 7-5. Tuck celebrated by walking toward the seats and flexing for the fans.
Akers' 25-yard kick on the final play of the first half gave the Eagles a 10-8 lead.
Carney made a 36-yard field goal for an 11-10 edge, but the Giants didn't score again.