Luke Kuechly knew Carolina's defense didn't have much bite earlier in the season.
The Panthers middle linebacker said that made Saturday all the more special.
Carolina limited Arizona to 78 yards and forced three turnovers in a 27-16 win, the franchise's first postseason victory in nine years. Those are the fewest yards ever given up in an NFL postseason game.
The NFL record had been held by the New York Giants, who limited Cleveland to 86 yards in 1958.
The Panthers (8-8-1) held Arizona to 12 yards in the second half, intercepted Ryan Lindley twice and sacked him four times in a dominating performance.
Carolina's defense has gone from 27th in the league in Week 7 to 10th entering the playoffs.
"We had a lot of new guys early on who had to get accustomed to each other," said Kuechly, the All-Pro who had a game-high 10 tackles and a key interception. "Now we're all together and communicating — and that's huge."
The Panthers had 386 yards, as Cam Newton overcame two turnovers and threw for 198 yards and two touchdowns and Jonathan Stewart ran for 123 yards and a score on a rain-soaked afternoon.
Newton was quick to deflect attention to his teammates on defense after his first career playoff win, calling their performance "lights out."
"When those guys play like that, it makes it easier on us on our part," Newton said. "Those guys did everything, turnovers, they stopped them. That is championship football right there and we've got to do our part offensively to put points up on the board."
The Panthers will play at top-seeded Seattle next weekend if Dallas beats Detroit on Sunday. If the Lions win, the Panthers play at Green Bay.
It appeared the Panthers wouldn't get the yardage record, but Arizona began lateraling the ball around the field on the final play and lost 19 yards.
It was a fitting end to the Cardinals' ineptitude on offense.
After a 9-1 start, Arizona's once promising season was undone by a rash of injuries, including to quarterbacks Carson Palmer and Drew Stanton. Lindley simply wasn't up to the task of leading a playoff team.
Trailing 27-14, Arizona recovered a Newton fumble and returned to the Carolina 8. But with a chance to get his team back on the game, Lindley fired over the middle but was intercepted by Kuechly, essentially sealing the Carolina win with 11:48 left in the game.
Arizona Coach Bruce Arians refused to pin the blame on his young quarterback.
"I thought he did great up until the first interception," Arians said. "He managed the game as well as he could. We didn't do a good job of putting ourselves in manageable third downs. But we got the big break and he tried to force one in that should have never been thrown."
The Cardinals finished the season 11-6, but lost five of their final seven games.
"As a team, we always fought," defensive tackle Frostee Rucker said. "It was always the next man up. At some point, we just didn't have anything left. Everyone should hold their heads high. Every person gave it their all, this whole season, win or loss."
Trailing by one at halftime the Panthers scored two touchdowns in a span of 92 seconds late in the third quarter to take control.
Rookie running back Fozzy Whittaker caught a pass in the flat from Newton, reversed fields and got a key block from Kelvin Benjamin to spring him for a 39-yard touchdown.
On the ensuing kickoff, Melvin White stripped returner Ted Ginn Jr., a former Panther, at the Arizona 3 and Kevin Reddick recovered for Carolina. A pass interference penalty on Tony Jefferson on third down gave Carolina a new set of downs, and Newton took advantage. He found wide-open fullback Mike Tolbert in the left flat for a 1-yard touchdown and a 27-14 lead.