If the Buccaneers lose, New Orleans (9-8) or Atlanta (7-10) would have won the NFC South in their season finale. Baker Mayfield and Tampa Bay won 9-0 with the Saints and Falcons on the field.
New Orleans may still qualify for the NFC wild card if Seattle and Green Bay lose later Sunday.
Jamaal Williams scored on a 1-yard rush in the last two minutes after New Orleans set up to kneel and run out the time. The Falcons and Saints coach Dennis Allen seemed irritated with the play.
For New Orleans, Carr tossed for 264 yards and rookie receiver A.T. Perry scored twice to double his season.
After his third straight loss, Atlanta's third-year coach Arthur Smith was questioned in the locker room.
Pro Bowl returner Rashid Shaheed caught a 39-yard touchdown catch for the Saints. On a disputed throw, Chris Olave scored 26 yards by tipping the ball to himself in the end zone. After returning from a Week 9 ankle injury, New Orleans running back Kendre Miller scored on a 3-yard run in the first half.
An ankle issue sidelined Atlanta quarterback Taylor Heinicke, but 2022 third-round pick Desmond Ridder made his 13th start. A first-quarter swing ball to Bijan Robinson for a 71-yard score down the left sideline capped his day.
Two turnovers contributed to second-half Saints scores, ruining Ridder's day. After returning as an injured replacement, defensive back Alontae Taylor intercepted Ridder after being benched for blunders on two explosive Falcons plays in the first half. Then Olave scored to give New Orleans the lead for good at 24-17 early in the third quarter.
In his first game since his Week 1 toe injury, defensive end Payton Turner recovered Ridder's shotgun fumble in the fourth quarter. That play set up Perry's second TD.
Ridder completed 22 of 30 for 291 yards and two scores. Robinson caught seven passes for 103 yards.
Ridder's third-quarter failed ball nearly got intercepted on fourth-and-goal.
One play after blocking defensive end Carl Granderson knocked Cordarrelle Patterson down from behind for a loss on third-and-goal from inside the 1, Atlanta squandered a crucial chance to get within one score.
Logan Woodside, who replaced Ridder late, was intercepted by Tyrann Mathieu. On his fourth interception of the season, the veteran returned it 74 yards before being stopped at the Atlanta 1.