LOUISVILLE, Ky. – Lamar Jackson’s Heisman Trophy is back home in South Florida.

Somewhere.

“Unmarked location,” the Louisville quarterback said with a chuckle, sitting in a meeting room in the Cardinals’ football facility last week.

Good strategy, Lamar. Reveal nothing. Because at this rate you can’t blame Jackson for wondering whether Heisman voters and college football analysts might try to retroactively take it back from him.

The familiar, build-them-up-to-tear-them-down machinery of American sports is running full-throttle right now on the native of Pompano Beach, Fla. The darling fresh face of 2016 is now the deconstructed known commodity of 2017.

Last month Fox Sports analyst Joel Klatt listed the top five quarterbacks in the nation, and Jackson wasn’t among them. Bruce Feldman of Sports Illustrated ranked his top five 2017 Heisman candidates and didn’t include him. Oddsmaker Bovada currently slots Jackson as the co-fourth choice, behind USC’s Sam Darnold, Penn State’s Saquon Barkley and Oklahoma’s Baker Mayfield, and tied with Ohio State’s J.T. Barrett. An anonymous ACC coach told Sports Illustrated last January that Jackson has “no shot” at being an NFL quarterback.

Has there ever been a more maligned, doubted and dismissed returning Heisman winner? Has a season spent producing 51 touchdowns and 5,000 total yards ever had less carryover buzz? Has a 3,500-yard passer who recorded a top 25 national pass-efficiency rating, without playing in a gimmick offense, ever been more widely questioned as an NFL quarterback prospect?

Johnny Manziel and Jameis Winston were not overly popular defending Heisman winners, but that was due to off-field issues. Jackson has none of those, to the best of anyone’s knowledge. He collected 79.5 percent of the Heisman vote, sixth-highest percentage in the last 50 years, yet all that support seems to have disappeared.

“It’s a little bit comical,” said Louisville coach Bobby Petrino, not looking at all amused by the comedy. “What Lamar did last year, I’m not sure we’ll see again.”

Petrino recited the statistics, which included breaking NFL star Philip Rivers’ Atlantic Coast Conference record for total offense yards per game, and the ACC mark for total touchdowns. But the coach also knows where much of the Jackson doubting originates.

“We didn’t finish like we wanted to,” Petrino said.

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That’s the biggest factor in this Jackson revisionism, with a late slide smudging memories of 819 total yards and eight TDs against Florida State and Clemson. In a sport that is overly influenced by what you did at the end of the previous season, Jackson spent the final three games besieged, bewildered, secretly injured and soundly defeated.

Louisville plummeted out of College Football Playoff contention with season-ending upset losses to Houston and Kentucky, then was trounced in the Citrus Bowl by LSU. In those games, Jackson was sacked 22 times, had four turnovers against the arch-rival Wildcats and completed less than 50 percent of his passes.

Jackson suffered a turf toe injury early in the Kentucky game, and he said it affected him all the way through spring practice and into May. But the biggest late-season problem was the combination of a collapsing offensive line and Jackson’s difficulties deciphering defenses.

While Jackson was stumbling, Deshaun Watson, Darnold and Mayfield were finishing their seasons with big numbers and big wins. And by January everyone wanted a Heisman refund.

Ask Jackson about going from dazzling to disrespected and he just smiles and shrugs.

“I wasn’t on the Heisman list last year [in August], either,” he said.

As Petrino pointed out, this year’s Lamar Jackson model may not produce the staggering statistics of 2016. That’s because the Louisville backs and receivers could be more reliable, after he had to do virtually everything himself last year. (For a comparison of supporting casts, consider that Clemson’s Watson had five offensive teammates on the all-ACC first team, while Jackson had zero.)

But this year’s Jackson could still be better than last year’s, even if the numbers aren’t as ridiculous. The potential areas of improvement:

• A greater grasp of opposing defenses.

Jackson’s reaction when watching video from 2016: “It’s embarrassing sometimes. I get mad when I see sacks and stuff like that. A lot of that was on me.”

Confusion reading coverages sometimes led to Jackson holding the ball too long, as he struggled finding second options or realizing that a play was a bust and throwing the ball away. So the coach Jackson calls “The Mastermind” worked with his quarterback on reads – specifically safeties and linebackers – during the off-season and spring practice.

Petrino is seeing tangible progress. It made his day recently in fall camp when Jackson corrected a receiver’s choice on an option route, correctly pointing out that he should have broken the route inside instead of outside.

“His knowledge is way ahead of where it was,” Petrino said.

• A better offensive line.

After watching Jackson run for his life against Houston and LSU, ESPN analyst Cole Cubelic went the opposite direction of many of his peers. He became more impressed by Jackson.

“Lamar Jackson winning the Heisman behind that offensive line might be the most impressive accomplishment I’ve seen in college football,” said Cubelic, a former Auburn offensive lineman whose Twitter breakdowns of line play have drawn a large following.

Petrino made an important staff change at that position. Chris Klenakis was moved to coaching tight ends, and Mike Summers returned to the fold from Florida. Summers coached some high-quality offensive lines during Petrino’s first stint at Louisville, from 2003-06.

If Jackson spends less time on his backside (a whopping 46 sacks in 2016) or sprinting away from unblocked rushers, it stands to reason he will spend more time completing passes or running to daylight.

• Improved mechanics.

Jackson’s occasional lapses in accuracy can often be traced to simple details, like the location of his right leg and the angle of his right arm. Petrino, a master at coaching the small physical tools of quarterbacking, focused on cleaning up those areas.

He wants Jackson’s right leg under his right hip, not splayed out behind the QB’s body. And he focused on Jackson’s delivery, reinforcing an over-the-top motion instead of dropping to a side-arm style.

“He’s really improved on getting on top of the ball,” Petrino said. “He takes pride in it now.”

When the mechanics are right, the ball is on the money. And that’s one reason why Petrino chafes at the notion that Jackson is a long-shot NFL quarterback prospect who may need to switch positions.

“He definitely can play [quarterback in the NFL],” said Petrino, who spent three seasons in the NFL as an offensive coordinator and one as a head coach. “No question about it. Take his running game and throw it away and he can still play in the NFL.

“He can make all the throws: go route, post, corner, he can stick the in cut, he can throw the deep out. All the dynamic highlight plays they show are him running the football, but you sit down and study his video, he can really throw it.”

That pure throwing ability first caught Petrino’s eye during Jackson’s second practice ever at Louisville as a freshman. He saw the 18-year-old snap his wrist, Vick-like, and fire off one high-velocity ball after another.

“We watched that and right away said, ‘Woooo, we’ve got something here,’ “ Petrino recalled.

So the raw ability to throw is not a concern. And the knowledge of the position is improving. According to one NFL scout, the greatest concern may be Jackson’s slight physique. In a league where many of the top quarterbacks are at least 225 pounds, Jackson needs to bulk up.

“I think he’s already shown that he can be drafted based off the Clemson game,” the scout said, referring to Jackson’s 457 total yards against the eventual national champions. “They’re going to worry about his size. Can he hold up? Is he big enough? He’s a slimmer build. He has physical talent, drive and ability to play in big games. Teams want to see how much does he really weigh.”

The answer, according to Jackson, is 212 pounds. That’s up at least 10 from last year, and the weight is needed to withstand the hits he took while running the ball 260 times in 2016.

Jackson’s NFL readiness will be hotly debated throughout the upcoming season. Just don’t expect him to be part of the debate.

“I can’t say nothing,” Jackson said. “You can’t worry about that. I’m not in the NFL. I’m playing quarterback at Louisville.”

He played it at a Heisman-winning level last year. But Lamar Jackson somehow still has a lot to prove to a nation that seems to have forgotten how good he was.

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