The US leg of the band’s No Filter tour had been delayed due to Sir Mick’s heart surgery.
But the frontman defied medical expectations with a quick recovery that even his bandmates hailed as “superhuman”.
He fronted the Rolling Stones’ comeback in Chicago on Friday 21 at the city’s 61,500-seater Soldier Field stadium.
But a heart specialist must be within feet on the singer when he is performing due to insurance requirements, according to the Mail on Sunday.
A source said: “There has always been a doctor on tour with the band – that’s a requirement of any major tour, particularly given the ages of the band members.
“But now Mick has undergone heart surgery, there is a cardiologist there too, just for him. The insurance company demands it just in case anything happens.”
It was three weeks before the Stones’ North American run was due to start that Mick called bandmates Ronnie Wood, Keith Richards, 75, and Charlie Watts, 78 — into his Miami hotel room.
Visibly upset, he told them he needed an urgent operation to fix a problem with his heart and was not fit to perform.
Despite the nightmare of rescheduling 17 gigs, there was never any question about it. They just wanted Mick to get better. Music could take a back seat.
Ronnie said: “Mick had the knowledge from his doctors that someday he’d have to take care of this problem with his heart — but he had no idea it would come up this quickly.
“He called us to his room and said, ‘I’ve got to do this now’. He felt so bad about it. We said, ‘Don’t feel bad, if it’s got to be done, do it, then we can carry on rocking’. And now we really are ready to rock — luckily.”
Speaking in Chicago in the band’s only UK interview since Mick’s surgery, guitarist Ronnie, 72, added: “The doctors said they’ve never operated on an athlete at 75 before — we had a really good laugh about that.
“He’s just so fit, he sets aside three hours a day to do exercise and that’s done him plenty of favors in later life. He’s superhuman really.
“Usually if this type of operation is done on a 75-year-old not in retirement they go back behind a desk. They’ve never had a case where the guy hasn’t had a desk job.
“He’s a medical marvel, is Mick.”
In fact, Ronnie reckons the legendary frontman is fitter than ever.
This article originally appeared in The Sun.