Atlanta — For the first time this season, there was no big comeback for Carolina. No clutch play at a key moment. No costly mistake by its opponent in the last few minutes.
The perfect start is over for Cam Newton and the Panthers.
After Julio Jones' spectacular 70-yard touchdown reception in the third quarter gave Atlanta the lead, the Panthers came up empty in two possessions in the final three minutes as the Falcons held on for a 20-13 victory on Sunday.
Carolina (14-1) got the ball for the last time with 90 seconds left and no timeouts remaining. Newton completed a 19-yard pass to Corey Brown on first down but fumbled when stripped by Vic Beasley Jr. on the following play. Adrian Clayborn recovered for the Falcons, wrapping up the win.
It was Carolina's first regular-season loss since Nov. 30, 2014, at Minnesota. The Panthers did not get into the end zone after their opening drive.
"That's unacceptable, particularly at this time of the year," Newton said.
Newton said coach Ron Rivera said the team played as if it was waiting for a turnaround that never came.
Newton, the Panthers' MVP candidate with the Superman celebration pose, was just OK. He threw for 142 yards and was held without a touchdown pass for only the second time this season. He ran for 46 yards, including an 8-yard scoring run on the Panthers' opening drive.
After that, Carolina's only points came on two second-half field goals from Graham Gano.
Carolina's 13 points set a season low. The Panthers had scored at least 24 points in 13 straight games.
"We're 14-1 now," Newton said. "We put ourselves in a situation that we can use this as fuel to the fire."
The Falcons (8-7) spoiled the Panthers' bid for a perfect season only two weeks after being humbled in a 38-0 loss at Carolina.
"I viewed this game as a measuring stick for us," Atlanta coach Dan Quinn said. "I wanted to see how our team would respond after the game up there."
Matt Ryan threw for 306 yards and one touchdown for the Falcons. Devonta Freeman ran for 73 yards and a TD.
Carolina needed a win or tie or an Arizona loss or tie against Green Bay to clinch home-field advantage for the NFC playoffs. But the Cardinals (13-2) cruised to a 38-8 victory over the Packers.
Jones got the best of his much-anticipated matchup with Carolina cornerback Josh Norman. Jones had nine catches for 178 yards, including the dramatic touchdown catch.
Jones reached above linebacker Luke Kuechly for the catch as Panthers safety Kurt Coleman slipped, leaving a clear path for Jones to the end zone. The play put Atlanta ahead to stay at 14-10.
"Julio made a great play on it," Kuechly said. "That's really all there is. I thought I was in a good spot, but he went up and got it."
Atlanta's Shayne Graham kicked field goals of 37 and 54 yards in the final three minutes.
Carolina trailed 14-10 in the fourth quarter when Ryan mishandled a shotgun snap from the Panthers 37. Norman recovered the fumble, setting up Gano's 47-yard field goal that cut Atlanta's lead to 14-13.
Carolina's defense drew two unsportsmanlike conduct penalties, including one on cornerback Charles Tillman that helped keep the Falcons' marathon touchdown drive alive on their first possession.
The Falcons were stopped on a third-down incomplete pass before Tillman became entangled with Atlanta wide receiver Roddy White. Tillman drew the flag to keep Atlanta's offense on the field for a 16-play, 80-yard touchdown drive that lasted more than 9 minutes. Freeman scored from the 4 on the first play of the second quarter for a 7-7 tie.
Rivera said he would talk with the league office about the penalty but said, "There's nothing we can do about it. We didn't get off the field. We're not making any excuses."