Jimmie Johnson adds Le Mans to his 'retirement' duties | KEN WILLIS

DAYTONA BEACH — Jimmie Johnson never promised anyone a quiet retirement.

A season on IndyCar road courses was followed by a year on roads and ovals, including the Indianapolis 500.

Next came news he’s joining the ownership group of a NASCAR Cup Series team and will drive a handful of races, including the upcoming Daytona 500.

Saturday unveiled the latest box to be checked by the seven-time champ.

He arrived at Daytona, on Rolex 24 day, to accept an invitation to drive in the world’s other — and oldest — 24-hour endurance race: Le Mans. And in a “Back to the Future” twist, he’ll do it in a NASCAR machine.

And do it in a machine prepped by his longtime boss, Rick Hendrick, and Hendrick Motorsports, with his former crew chief Chad Knaus overseeing the project.

"When Rick called, I couldn’t resist the opportunity," Jimmie said Saturday. "Going to Le Mans with this team, …. It’s really a special opportunity.

“I’m super thrilled — it’s been at the top of my bucket list to compete in the 24 Hours of Le Mans someday,” he added.

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Mike Rockenfeller and Jenson Button were also introduced Saturday as Johnson’s Le Mans co-drivers. The grouping brings together champions from three very different racing disciplines — NASCAR, the World Endurance Championship, and Formula One.

This is the final and splashiest piece of the NASCAR-to-Le Mans package. Since 2012, Le Mans has reserved one starting spot for “innovative cars” and dubbed it the “Garage 56” entry. The Next Gen stock car, which debuted in NASCAR last year, is a far cry from the rocket-like Delta Wing — the original Garage 56 effort in 2012 — but it’s certainly innovative in the stock-car world.

Even more innovative for the June 10-11 Le Mans 24, since by rule it has to incorporate hybrid technology throughout the car’s innards.

It’s probably no coincidence this is happening at a time when the racing lords of North America and Europe aren’t just preaching synergy, but trotting it out there — this weekend’s debut of LMDh prototype cars and GTP class, which meets both continents’ specs, has hogged the biggest Rolex 24 headlines.

The three-man roster is “everything we could’ve dreamed of,” says Jim France, who oversees IMSA as well as serving as CEO of NASCAR.

“We are honored to have these world-class champions help bring the sights and sounds of a NASCAR race car to fans in Le Mans, and across the world,” he adds.

That’s the driving intention of this whole deal — “to put NASCAR on a more global stage,” says IMSA president John Doonan.

A major component of that, obviously, would be the driver lineup. There was no shortage of interested cockpit jockeys.

“We all had a lot of new friends we didn’t know we had,” Doonan says. “From all different disciplines — sports cars, stock cars ….”

The shopping list was eventually whittled down by attaching necessities and desires.

“Who can put us in the best place for performance on the track, the best place to reach the biggest audience, and who has the right attitude,” Doonan says.

Rockenfeller brings the sports-car chops, having won the 2013 World Endurance Championship, Europe’s premier series. The German racer also, by the way, has overall 24-hour wins at both Le Mans and Daytona.

“It’s been a great journey so far,” says Rockenfeller, who was no big surprise either, given the hours of testing he’s given to the project.

But if it’s worldwide cachet you crave, it’s hard to beat a Formula One champ. Button’s F1 title came in 2009, when the Brit bagged six of his 15 career World Championship victories. He proved he’s up to speed with an overriding theme of the effort when he talked of bringing it to “current and future NASCAR fans from around the world.”

Next up: A two-day test at Daytona on Tuesday and Wednesday, followed by a full 24-hour shakedown next month at Sebring. While Jimmie and "Rocky" have turned many laps in the Le Mans car, Tuesday will be Button's first time and, given his F1, highest-of-high-tech background, might create a bit of culture shock.

Bring it on, he said Saturday.

"It’s really special to be here," Button said. "I’ve always thought of myself as a racing driver. I finished my F1 career and looked for new challenges. I'm very excited to work with this all-star team and I think we can achieve something special."

— Reach Ken Willis at ken.willis@news-jrnl.com

This article originally appeared on The Daytona Beach News-Journal: NASCAR to Le Mans, with Jimmie Johnson sharing the Next Gen wheel