It definitely wasn't Russell Wilson, who didn't even make it through a full year under Payton before the Super Bowl-winning head coach knew that the Broncos needed someone different in Denver.
"Russell Wilson wasn't terrible last year … he did not run an offense Sean Payton wanted to run," Denver Post columnist Troy Renck exclusively told talkSPORT.
"Russell Wilson's at his best throwing moon balls and scribbling outside the lines.
"Sean Payton wants Drew Brees. He wants a quarterback that plays on time and on target, and that's what he sees in Bo Nix."
Wilson has resurrected his career with Pittsburgh, taking over midseason for Justin Fields to lead Mike Tomlin's Steelers to a 10-4 record and a playoff spot.
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But Nix has been a rookie revelation for the Broncos, paying off on Payton's risky draft-day gamble and rivaling Washington's Jayden Daniels as the leading candidate for NFL Offensive Rookie of the Year.
The former Auburn and Oregon QB can push Denver to 10-5 with a road win over Justin Herbert's Los Angeles Chargers on Thursday Night Football.
"He's smart, he's disciplined, he basically has no vices," said Renck, describing a rookie QB who's completed 63.6 percent of his passes for 2,972 yards, 20 touchdowns, 11 interceptions and an 86.1 rating.
"He doesn't curse. He's tied to his football, his family and his faith -- he keeps everything very simple."
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Nix's precision was a breakthrough moment for Payton, who won it all in 2009 by getting the best out of Brees and the New Orleans Saints.
A head coach with a career 169-103 record watched Nix be on target for 84-of085 passes during an NFL Draft pro day at Eugene, Oregon in March.
Nix had been benched in college and bounced across America trying to prove that he was an elite quarterback.
After becoming frustrated with Wilson's inability to play within his system, Payton became fixated on a draft prospect who was once "miserable" at Auburn.
"Bo started calling protections (at Oregon) -- Bo was basically the offensive coordinator on the field," Renck said. "He brought a lot of that to the Broncos."
Nix also brought an intangible that couldn't be created by a coach or manufactured during training camp.
Caleb Williams, Drake Maye, Micahel Penix Jr., J.J. McCarthy and Daniels were all off the board while Nix waited to have his name called.
Payton knew he had to have his next Brees in Denver, and the Broncos didn't hesitate to select Nix with the No. 12 overall pick.
"His teammates will tell you the secret sauce with Bo Nix is discipline, both in a game and outside," Renck said.
"He's able to blend humility with confidence. He's not overstepping his role.
"This is a team with a lot of older guys on offense... so he only talks when he needs to. He doesn't overcoach and guys love that about him.
"He just waits and then every once in a while, he jumps in."
When Nix got in Payton's face toward the end of a 34-18 home win over the Las Vegas Raiders in Week 5, Denver's head coach knew once again that the Broncos had made the right decision.
A tense sideline confrontation saw the rookie QB avidly challenging his Super Bowl-winning coach with TV cameras rolling.
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It was a win-win for Nix and the Broncos.
"Yelling at Sean Payton, teammates love that," Renck said.
"Even Payton loved it, because he loves the creative friction -- he wants you to come back at him.
"That's the day he became the quarterback and then the way he played at Kansas City and even Baltimore... he was their best player on the field.
"Not on offense or defense, the best player on the field."
Nix must finish strong in 2024.
But he's already proved that Payton was right in letting go of Wilson and investing in Denver's best QB hope since Peyton Manning was in orange.
"Now he's just got to get to the finish line," Renck said.
"Teams are making adjustments these last two games. I think he's pressed a little bit.
"They need to slow the game down. Sean Payton needs to push the brakes a little bit and get boring again.
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"They need to run the football a little better to be fair to Nix, because when Nix gets into trouble they drop back 40 to 45 times -- that's not fair to him as a rookie."
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