– He is forever skinny, eternally energetic and inexplicably ageless. Until now.

In March, as Mick Jagger was getting his mandatory physical exam before the Rolling Stones embarked on their North American stadium tour, an issue with his heart was discovered. Stop the tour! Sir Mick, at age 75, needed a new heart valve, something not uncommon for aging baby boomers but alien for the poster child of enduring rock ‘n’ roll.

Two surprisingly quick months after the heart procedure, Jagger and the world’s greatest — and oldest (and richest) — band are back, taking to sold-out Soldier Field on Friday night.

After two legs in Europe in 2017 and ’18 in front of 1.5 million fans, the No Filter Tour returned with more curiosity than ever about the Stones. It wasn’t the usual proverbial question of “Would this be the last time?” No, it was, “Does he move like Jagger?”

On the opening “Street Fighting Man,” the frontman, hungry to prove himself, took the stage in fighting form. All rubbery legs, he pranced, punched and primped and then started skipping down the runway before bursting into a full-on sprint like a breakaway halfback headed for the Chicago Bears’ end zone.

In his first performance in 11 months, Jagger busted more moves than usual, adding locking and popping plus hopping on one leg to the usual rooster strut, mincing sashaying, shadow boxing, pirouetting, twisting and shouting. You know the Mick moves.

Thirty-five days short of his 76th birthday, the singer with the flowing, feathery hair framing his weathered face looked almost too skinny for his slacks. We should all be so healthy.

Although he never said anything about his health, the rejuvenated Jagger was his usual chatty self. He pointed out that this was the band’s 38th show in Chicago and eighth time at Soldier Field. He even dipped into some local politics, giving a shout-out to the new Mayor Lori Lightfoot, who was in attendance, according to Jagger, and joking that he was sorry that Alderman Ed Burke, who is under federal indictment for corruption allegations, couldn’t make it.

During a brief acoustic set, the Stones offered the ballad “Angie,” and when Jagger sang “ain’t it good to be ah-li-ai-ai-ai-ve,” you felt he meant it.

Vocally, Jagger was assertive and spirited, finding a deep, twangy affected voice on “Dead Flowers,” a gorgeously soulful falsetto on “Miss You” and an affecting croon on the ballad-y beginning of “Can’t Always Get What You Want.” And he ended “Sympathy for the Devil” with joyous “whoop-whews” that floated over the 60,000 singalong fans.

“Honky Tonk Woman” was bursting with energy — and featured an animated video of a dolled-up woman squeezing an anatomically correct heart removed from some guy’s chest. The symbolism was hard to ignore.

Jagger’s camaraderie with his mates seemed palpable as he danced down the runway with guitarist Ron Wood during “Miss You” and gleefully blew his harmonica in guitarist Keith Richards’ face during “Midnight Rambler.” Those two extended songs were the highlights, as Jagger — and the band — got lost in the music instead of just performing like Mick Jagger Rock Star.

“Gimme Shelter” turned into a chilling vocal and physical pas de deux between Jagger and backup vocalist Sasha Allen as they threw down on the runway extending from the mammoth stage.

Enough about the old and improved Jagger. How were the other aspects of the show?

For opening night of a 17-concert tour (now set to end Aug. 31), things went rather smoothly (though Jagger forgot to introduce longtime keyboardist Chuck Leavell). The band seemed tight and efficient, with Charlie Watts’ masterful drumming driving this unstoppable 57-year-old engine. The saxophones of Karl Denson and Tim Ries added textures and depth, especially on “Before They Make Me Run.”

On the whole, the players clearly let Jagger be the focus, as has long been the case, though Richards and Wood (whom Jagger playfully dubbed “the Monet of the Magnificent Mile”) had their moments in the spotlight.

Richards has never sounded in better voice — clear and almost forceful — than when he delivered “You Got the Silver” and “Before They Make Me Run.”

Too often, though, their guitars were trebly and too bright. Richards did manage to find darker tones on “Satisfaction.”

By the by, both guitarists had new looks: Their foreheads were visible for a change, with newly brown-haired Richards eschewing his usual bandanna and Wood opting for a blow-dry feathered ’do instead of his trademark rooster cut.

The 20-song set list was perhaps too predictable, with 1989’s “Sad, Sad, Sad,” a slice of slightly twangy pop, being the only surprise. Where were the blues tunes from 2016’s “Blue & Lonesome” covers album? Especially in the home of the blues. Or maybe a track that the Stones recorded at Chicago’s legendary Chess Studios back in the day?

Still, thanks to Jagger’s refreshed and purposeful performance, the 122-minute concert was one of the Stones’ more potent efforts in their stadium era.

Clearly, for Stones fans, there’s no need to have a nervous breakdown over Jagger’s health. Apparently, you can never break the heart of this Stone.