MIAMI — It was in eighth grade, when the layup line at Envision Academy turned into a dunk contest, so Keshad Johnson, then “13 or 14,” decided why not?

“It was just all the guys on the varsity team were going for it, and I was an 8th grader. I was trying to go for it,” he said.

First dunk.

Of many.

The pathway to Saturday’s dunk contest during All-Star Weekend in Los Angeles.

Since that moment back home at Oakland, Calif., Johnson has taken his dunking skills to San Diego State, Arizona and now on to the NBA with the Heat, where his pregame thrill shows and late-game detonations in mop-up duty drew enough attention to be elevated to Saturday’s showcase.

While no longer a star-studded spectacle, the dunk contest has gone a long way toward elevating NBA journeymen to better-known quantities, with this year’s field including similar types in San Antonio’s Carter Bryant, the Lakers’ Jaxson Hayes and the Orlando Magic’s Jase Richardson.

The irony with players of such limited pedigree is that Johnson learned of his selection while heading out for seasoning with the Heat’s G League affiliate, the Sioux Falls Skyforce.

“Right before I went to Sioux Falls, they told me like two days, like a day before,” he said. “Actually, yeah, that night before they told me I was going to be at a dunk contest. So, I ain’t really got too long to practice, but I’m going to go out there and do what I do.”

Getting up to speed, Johnson said, wasn’t an issue.

“For sure, for sure, yeah, yeah, yeah. I’ve done dunk contests in high school and college,” he said.

Asked for his highlight of such previous moments, he said, “All of the moments, you know, just being able to showcase my God-given ability. So, I take pride in the dunk contest, just going out there and having fun and being creative, seeing everybody use their form of art.”

The last time a Heat player was in the dunk contest, Heat wing Jaime Jaquez Jr. two years ago dunked over former Heat center Shaquille O’Neal.

So what does Johnson have in store?

“I got something nice, I got something nice,” he said. “I don’t want to speak it into existence yet. It’s going to happen, though.”

To a degree, Johnson, 24 is arriving a year late to the showcase, with last year’s event held effectively in his childhood backyard, in San Francisco. But it’s not like Los Angeles isn’t driving distance.

“Yeah, I mean, same thing. You know, I didn’t get the opportunity last year, but this year, It’ll still be in Cali. That’s all you ask for,” Johnson said.

As the dunk contest has moved from headliners to prospects, the risk of the competition has been coming to be defined solely as a dunker, as was the case for former Heat dunk champion Harold Miner, and even reigning three-time dunk champion Matt McClung; who largely has toiled in the G League.

Johnson said he understands potentially getting tagged as a one- (or multiple-)trick specialist.

“It’s absolutely important, you know, just showing that you can do everything, showing that you’re an overall pro, you know,” he said of his overall game,  a significant factor in light of this coming summer’s free agency.. “But also getting a dunk contest under your sleeves, that’s also good, too.”

In fact, Johnson said it is the game action where he feels the greatest freedom for his creativity.

“It’s just second nature, for real,” he said, his effervescent personality featuring playful barking on the bench and in the locker room. “It’s just second nature. I’m not really just thinking too much about doing a dunk. I’m just going out there and doing what I do.”

For the Heat, there already have been ample auditions from the player nicknamed Showtime.

“We see it after practices, some of these dunks he does,” coach Erik Spoelstra said. “He can take off from right inside the free-throw line. He can do a lot of trick dunks. And he’s also really starting to figure out how to weaponize that athleticism, and show it more in the game of basketball where it’s not just a dunk contest.”