FLOWERY BRANCH, Ga. >> The Atlanta Falcons returned from their bye week Monday and find themselves a game out of first place in the NFC South with four games to play.

With the playoffs on the line, the Falcons are set to hand the football over to rookie quarterback Desmond Ridder, who has not played a down during the regular season.

“We did make a switch at quarterback; Desmond Ridder will be the starter,” Falcons coach Arthur Smith said Monday. “It’s a performance-based decision.”

The Falcons (5-8) will play the Saints (4-9) at the Superdome on Sunday.

“If I thought the moment was too big for him, I wouldn’t put him out there,” Smith said.

The Buccaneers (6-7) are in first place and host the Bengals (9-4) Sunday. The Panthers (5-8), who have won three of their last four games, will host the Steelers (5-8), also on Sunday.

“We are trying to get over the hump in some of these close games,” Smith said. “Where we are trying to push the offense, we felt like it was (the) best decision where he’s at, where the team is at, as we prepare to go down to New Orleans.”

Former starting QB Marcus Mariota was not with the team as it returned from the bye week. The Falcons signed quarterback Logan Woodside off Tennessee’s practice squad.

“(Mariota) has a chronic knee that he wants to get evaluated,” Smith said. “It has nothing to do with this decision. He’s not here right now … I anticipate him going on (injured reserve).”

Ridder, who was taken 74th overall in the third round of the 2022 NFL draft, has run the scout team all season and tried to master the Falcons’ game plan in case he was needed. He will replace Mariota, who was viewed as a stopgap quarterback from the time he was signed a few hours after the team traded longtime quarterback Matt Ryan to the Colts.

The franchise elected to pivot at quarterback over the offseason, when it tried to trade for Deshaun Watson, the former Gainesville High and Clemson standout who was embroiled in more than 20 sexual misconduct cases. Watson, the former Falcons ballboy, was traded to the Browns. After serving an 11-game suspension, Watson is 1-1 as a starter with the Browns.

Ridder and Mariota were notified of the move Thursday.

Running back Tyler Allgeier said more than a couple players worked out with Ridder over the bye week catching passes.

“I’m excited to see what Desmond can do,” Allgeier said. “It should be really good. I’m excited for him.”

Ridder was not present during the open media portion of practice Monday. Allgeier is his locker mate.

“He’s just excited for his opportunity,” Allgeier said.

Woodside was on site and will wear jersey No. 6.

“The first reaction was that I was super excited,” Woodside said. “Super grateful for everything from being in Tennessee the last four years. They definitely helped me be ready for this opportunity. Just super excited to be down here. I know some of the guys on the team. I’m excited to get going and try to help in any way that I can.”

Ridder played in all three exhibition games. He completed 34 of 56 passes (60.7%) for 431 yards, three touchdowns and two interceptions. He had a passer rating of 87.7.

Ridder, who guided Cincinnati to a 44-6 record and a trip to the College Football Playoff, flashed some of his winning style in his first NFL game. In the exhibition opener against the Lions, with the Falcons down 23-20, Ridder tossed a 21-yard touchdown pass to Jared Bernhardt with 1:30 to play to pull out the victory.

The Falcons lost the second exhibition game 24-16 to the Jets. Ridder completed 10 of 13 passes for 143 yards, no touchdowns and no interceptions. He finished with a passer rating of 112.

Ridder played 53 of the 65 offensive snaps (82%) in the exhibition finale against the Jaguars. He completed 14 of 21 passes for 185 yards, a touchdown and two interceptions. He finished with a passer rating of 70.6 in the 28-12 victory.

The Falcons are hoping that Ridder can be more productive in the passing game than Mariota, while also maintaining the league’s No. 4 rushing attack.

As the Falcons have dropped four of their last five games, the cries from the fan base to play Ridder have grown louder. Over the bye week, the Falcons elected to make a change.

Mariota has completed 184 of 300 passes (61.3%) for 2,219 yards, 15 touchdowns and nine interceptions. He has a passer rating of 88.2. Under Mariota, the Falcons averaged 155.7 yards passing per game, which ranks 31st of 32 teams in the NFL.

With Mariota’s rushing yards (career-high 438 yards), the Falcons rank fourth in the league, averaging 158.9 yards per game.