With 9:55 remaining, Manning lofted a perfectly thrown ball down the middle of the field, hitting Mario Manningham in full stride for a 27-yard touchdown as the wideout split double-coverage in the back of the end zone to account for the final score.
It was the third touchdown pass of the day for Manning, who completed 23 of 32 for 277 yards, but symbolic of so much more: With their league-worst rushing attack pounding out a season-high 172 yards, and with a resurgent defense twice snuffing out the Falcons' offense on 4th-and-1, the Giants are hitting their stride in a way that's reminiscent of the team's championship run at the end of the 2007 season.
"It's right on par," says linebacker Mathias Kiwanuka, a holdover from the Super Bowl team that reeled off four postseason victories behind a dominant ground game and defense. "In terms of intensity and hitting our stride, it's right on par."
In winning their first playoff game since upending the unbeaten Patriots in Super Bowl XLII, the Giants finally showed themselves to be a complete team after relying on Manning's arm (he threw a career-high 4,933 yards) for most of 2011.
The defense, which had 11 sacks in two must-win games to close out the regular season, held Atlanta to a season-low 247 yards of total offense while limiting running back Michael Turner to just 41 yards -- less than half of his per-game rushing average (83.8).
The tone was set on the first play of the second quarter.
Facing 4th-and-1 at New York's 24-yard line, the Falcons went for a first down instead of kicking a field goal in a scoreless game, only to have quarterback Matt Ryan's sneak attempt stuffed for no gain by tackle Linval Joseph and linebacker Michael Boley.
With just over four minutes left to play in the third quarter -- and trailing only 10-2 -- the Falcons went for it again on 4th-and-inches, from the New York 21. Ryan again was stopped for no gain, this time by defensive end Jason Pierre-Paul and linebacker Chase Blackburn.
"We made a statement that you can't run the ball on us," Pierre-Paul said. "I feel like it's disrespectful for them to go for it, but you see the outcome. They were in field goal range, why not kick the field goal? You're not losing by much."
Three plays after that second stop, the Falcons found themselves in a deep hole when Manning connected with Hakeem Nicks on a short pass over the middle that turned into a 72-yard touchdown and a 17-2 lead.
Nicks, who had been held to 76 yards or fewer in each of the Giants' final three regular season games, finished with six receptions for 115 yards and two touchdowns, including a four-yard TD late in the second quarter that put New York up 7-2.
"We never got into a rhythm. We never moved the ball consistently," said Ryan, who completed 24 of 41 for 199 yards, and was sacked twice for a loss of 16 yards. "We just didn't make the plays on crucial third and fourth downs ... I've got to do a better job of finding the crease [on sneaks] and trying to find a hole to get in there and get the yard. I didn't do that."
The Giants, for once, had little problem moving the ball on the ground, averaging 5.5 yards per carry while Brandon Jacobs (92 rushing yards) and Ahmad Bradshaw (63) each broke a run for at least 30 yards.
"I think we're the toughest team in the league," Bradshaw boldly declared afterward.
The true measure of that toughness will be determined next weekend when the Giants travel to top-seeded Green Bay for the NFC divisional round, but Big Blue won't be a complete long shot. New York almost knocked the Pack off its pedestal in Week 13 when Green Bay was still unbeaten, ultimately losing 38-35 at home -- a game the Giants' D played without All-Pro defensive end Osi Umenyiora.
Umenyiora, who missed all of December with an ankle injury, returned for the regular season finale against the Cowboys and recorded two sacks. He picked up another on Sunday, putting a punctuation mark on the Giants' victory by leaping over tackle Will Svitek and sacking Ryan on the Falcon's final offensive play, with 61 seconds remaining.
"The two fourth-down stops were just outstanding. Those plays that our defense made really inspired everybody," Giants coach Tom Coughlin said. ""If we continue to play defense like that, we can make ourselves heard in this tournament."
At the very least, they already have the Packers' attention.