Bernie Ecclestone has not looked his best in recent months. The wiry, diminutive billionaire with the Paul Weller hairdo and John Lennon glasses, who has run Formula One like a personal fiefdom for 30 years, has been looking, well, his age. At 78, ten years down the line from a heart bypass and with a schedule that requires him to fly all over the world, it was hardly surprising that it could be starting to tell.

It was not just the schedule. The man who almost single-handedly turned Formula One from a ramshackle circus into a tightly organised, global, commercial success story had been dealing with the trauma of breaking up with his wife of 24 years, Slavica, a statuesque Croatian former Armani model. And friends of the couple could see that it was getting to him. As one put it: “Bernie is beginning to show his age.”

But as the Formula One season roars into life in Melbourne with the Australian Grand Prix on Sunday, the chief executive officer of Formula One Management has returned to the fray firing on all cylinders. Last week he and his old mucker, Max Mosley, the president of the FIA, the world governing body, stunned motorsport by announcing a stringent budget cap for next season. Since then, Ecclestone has been pulling journalists in on a daily basis to make sure everyone is up to speed on the way “the little guy” (as some call him in the paddock) sees the future. In my case it was an invitation to lunch at his favourite gastro-pub, just around the corner from his London office in Knightsbridge.

Dressed immaculately, as always, in a blue suit, white shirt and blue woollen tie, Ecclestone leads the way into an establishment in which he is one of the family. He heads for his favourite table next to the bar and takes his customary seat, from where he can keep an eye on the door. You can tell he has briefed the waitress on timing — the fastidious Ecclestone hates to waste a minute, whether at lunch or in a business meeting. The menu is in my hand for no more than 60 seconds before she is ready to take our order. Ecclestone has soup and chicken Caesar salad.

Before long, the subject of the collapse of his marriage comes up — not raised by him, I should add — and you cannot fail to be struck by his equanimity in the face of a blow that would floor many septuagenarians. Ecclestone is one of the funniest people you will meet and even this personal crisis is not off limits on that score. How, I wondered, is he coping with the reality that he may have to spend the rest of his life on his own?

“Who said I was going to do that?” he shoots back, with a twinkle in his eye from behind the Giorgio Armani-framed lenses. And what stage has the divorce reached? “We have to discuss who has the custody of the dogs and things like that,” he offers, deadpan. Do you want them? “No, she can take the dogs.”

There are, of course, some very serious issues to wrap up. When your total wealth is greater than the gross national product of a fairly large African country, divorce is bound to be complicated. In Ecclestone’s case, there is the tricky issue that much of his estimated £2.4 billion fortune is in a family trust in Slavica’s name and he needs to get quite a lot of it back. But he seems unworried. “I haven’t done anything about it — I hope she’s sensible enough to know that I would need a few quid to live the life I am accustomed to,” he says.

He is equally good-natured about the reasons behind the split, even if his denial that he has no regrets rings a little hollow. Ecclestone is a workaholic and everything else — his marriage and his two grown-up daughters, Tamara and Petra — have had to come second to the demands of the office.

With the girls having left home, Slavica’s role as housewife, mother and launderer — Ecclestone says she used to love doing the washing — was largely completed. Yet Ecclestone could not stop himself returning to the job he adores and has said he will leave only in a box. “So she’s still 50 years old, she’s good-looking, she’s got a few quid in the bank, she might as well start changing her life. I don’t blame her for that,” he says.

Later, as he admits he has thrown himself back into his work, taking refuge in the office from the turmoil in his private life, he comes as close as he ever will to acknowledging that things could have been different. “The question is, or should be, had this not happened with Slavica, would I have slowed down doing what I am doing and I think the answer to that is yes,” he says. “In fairness to her, it’s something I’ve been promising for a couple of years.

“Things have changed and changed and I haven’t been able to run away. Maybe if I had run away, slowed down a bit two years ago, maybe we would still be together and it wouldn’t have happened.”

Eyeing the season ahead, Ecclestone is at his mischievous best. For him, Formula One is a “show” and, as its ringmaster, it is his job to make sure the audience is entertained. So if things are looking a little predictable, he will release a wild tiger every now and again, just to keep everyone on the edge of their seats.