Jim Leonhard trusted his eyes.

Such faith is foundational for any good defensive back.

So when the 41-year-old’s smooth-sailing, fast-rising college coaching career took a big hit late in 2022, he first stepped back. Then he thought about what he’d seen and let it guide him toward his next landmark: the NFL.

Leonhard kicked off this stanza of his coaching career in February when Sean Payton hired him as Denver’s secondary coach and defensive passing game coordinator. Payton tried to hire him a year earlier, too, shortly after Leonhard thought he had the University of Wisconsin head coaching job locked up, only to watch the school hire Luke Fickell instead.

In the past 12 months, Leonhard experienced plenty of new things but also one familiar theme: A lot of people had interest in hiring him.

So why eventually say yes to Payton and the Broncos? He leaned on an old scouting report from 11 years ago, when he spent April through August 2013 on New Orleans’ roster under Payton.

“He cut me, so he had to overcome some things there,” Leonhard told The Post with a smile. “But it was a unique enough experience for me. It was later in my career, but the way he talked, the way he communicated with the team and set the vision for what the program was all about, it felt a little different and it piqued my interest. …

“(Denver) wasn’t a team that I necessarily studied or knew everything about. A little bit of trust in his track record and what I had seen and been around as a player and other coaches I’d talked to that have been around him. Just thought it was a unique opportunity to come into.”

Leonhard’s reputation is as a strong teacher but also a quick study. It’s safe to assume that he’ll not only be working to help a mostly young Broncos secondary round into form under Vance Joseph, but will also be watching and learning from the veteran coordinator and from Payton. After all, Payton likes collecting assistants with upside and thinks Leonhard is the latest who possesses plenty.

“I’ve kind of known him for a while,” Payton said, “And he’s one of those guys — not only myself, but I would say a number of people in the league — have tracked and said, ‘This guy has got a real good future as a coach in this league.’”

Jump to the NFL

Leonhard almost didn’t get a start in the NFL at all.

It didn’t look like he’d need one.

After engineering several top-flight defenses at Wisconsin between 2017 and ’22, Leonhard became the team’s interim head coach in October 2022, when Paul Chryst was fired amid a slow start.

Leonhard spent years rebuffing all manner of offers — including the Green Bay Packers defensive coordinator job in 2021 — and now had his hands on the head job at his alma mater, where he had been a three-time All-American safety.

“I went into it with pretty clear eyes as far as what being a head coach entails and everything involved,” he said. “You learn very quickly on how clear you have to communicate. You learn very quickly on the amount of people you have to manage. It’s a fun challenge. It’s a lot. It’s something you can’t turn off. There were no big shocks on it. To go into a situation where you’re the interim coach, you know things aren’t going well, right? You go into a team that’s reeling, kind of on its heels, and you go, How do I settle this thing down and then create the vision on how we’re going to turn it?”

The Badgers went 4-3 down the stretch and it was widely assumed, even reported, that the permanent job was his. Then athletic director Chris MacIntosh instead swung a late deal to hire Luke Fickell away from Cincinnati.

An old mentor

Bret Bielema remembers clearly the first time he met Leonhard.

Bielema was the incoming defensive coordinator at Wisconsin in 2004 and Leonhard a senior safety for the Badgers with 18 interceptions already to his name. Head coach Barry Alvarez told Bielema that if he wanted to get a pulse on the defense, he should get to know its best player.

“I didn’t know anything about Jimmy. Back then there wasn’t much Google research,” Bielema, now the head coach at Illinois, told The Post recently. “I read his bio and watched his film and thought, ‘This guy’s pretty good.’ So I sat down with him and spent an hour explaining our defense, the strengths and weaknesses of our basic calls and what it would allow him to do and showcase.

“And literally, I very quickly realized that this kid processes, learns and understands better than any player I’d ever been around at that point.”

Case in point: Later that year, Leonhard logged two interceptions in the first four minutes of a game against Iowa.

“Iowa had a scheme they’d shown and they knew we’d probably be on to it, so the very first third-down play they had a different alignment than they’d ever run but ran the same play conceptually. Jimmy picked it off,” Bielema recalled.

The offense gave the ball back to Iowa so quickly there was no time for a sideline debrief.

“I send the defense back on the field and Iowa did it again and Jimmy intercepted it again,” Bielema marveled. “This guy literally auto-corrected to two things he’d never seen just by (making an) identification that we’d never discussed.”

They stayed close after Leonhard went undrafted in 2005 but cracked Buffalo’s roster as a rookie. Bielema eventually became UW’s head coach. Leonhard would return to Madison each offseason with a notebook full of learnings from Rex Ryan or whichever coordinator he played for that season.

Bielema made it clear: “Whenever you get done playing, brother, I’ve got a job for you.”

Football life happens in funny ways, though, and the two didn’t link up until 2023. Leonhard had talked with Payton about a job on the Broncos’ staff but needed to have hip surgery and wasn’t sure he wanted to uproot his young family so quickly after the end of his tenure at Wisconsin. So Bielema moved quickly to hire Leonhard as an analyst. He could spend Monday through Thursday at Illinois helping Bielema’s coaches, then spend the rest of the week at home.

“He had an immediate impact on everybody in our building,” said Bielema, who would have gladly taken him back this year except, “I knew he kind of wanted to get into the NFL world.”

The place turned out to be Denver, where Leonhard once signed during training camp in 2012, made the team and ended up with a pair of interceptions over 16 games (one start).

“Incredibly gifted’”

P.J. Locke casually slips into first-name basis.

“I spend a lot of time with Jim,” he told The Post this month. “Literally every day after practice I have one-on-one sessions with him and it’s just for my own sake.”

Locke’s one of several young players with a lot on the line as the secondary gets to know its new coach. Locke pencils in as a starter next to Brandon Jones, especially as Caden Sterns continues to rehab from a 2023 torn patella tendon, and said he’s already benefiting.

“Some of the stuff he’s teaching me, I’ve never thought of. It makes so much sense,” he said. “And now it’s just taking what he teaches and bringing it to the front and trusting it. He brings a different dynamic of trusting in your ability, trust in what you see, trust in what the quarterback is giving you, trust in the routes that you see and that are developing and the concepts that you see.

“Trust it. Don’t be afraid to make a mistake. Sometimes you’ve got to be aggressive. When you’ve got a coach like that, it can really help you play loose.”

For several years, Parker stood as one of the few constants on Denver’s defense. Now in Year 2 under Joseph, the corners and safeties have a new voice in the room.

“I’ve got a ton of respect for Vance and what he does on defense,” Leonhard said. “I think I can be a big asset for him and really help get his vision for what this defense should be and how we want to play. I think I can really help him with that, and that’s what I’m excited for.”

Well, that and “being able to kick (the recruiting in college football) to the side and really focus on the relationships with coaches and game-planning and the players,” he said.