It was American author Mark Twain who said that fact is stranger than fiction. It must be, he said, because fiction is limited by the human imagination, whereas reality is limited by nothing.

The Valentino Rossi story is way too far-out to be fiction. If someone wrote a Rossi-inspired movie (a kind of two-wheeled Days of Thunder) it would get laughed out of the cinemas. What a load of Hollywood nonsense – that kind of stuff never happens in the real world.

A decade ago you could have got away with writing a believable film about Rossi. Indeed during the first era of his pomp – the first half of the last decade – I used to think his life would make a great film, so long as you made up the final scenes, which would reveal him in a dingy London basement nightclub (he was living in London at the time, because he loved the architecture, ahem) and having the time of his life with some wild young Bohemians.

Then he would slide right off the rails, miss a race after forgetting to set his alarm, get sacked and end up blowing his fortune back in London, having hooked up with a rather less salubrious bunch of underworld glitterati. Next would come the early morning epiphany, encouraged by a slight case of bankruptcy, and he would fight his way go back to racing, his rivals sniggering as he walked onto the grid, all baggy-eyed. And once again he would destroy them. Roll credits…

Rossi’s first era of pomp did end, but not like that. His darkest moment was less dramatic: in 2007 he was beset by Casey Stoner, Ducati, Bridgestone, girlfriend problems and a €19 million bill for tax-dodging.

Some people in the paddock already believed he would never win another world title. And yet he bounced back to win the crown in 2008 and 2009. Then everything really fell apart: he broke a leg, got hung out to dry by Yamaha, who had decided his bitter rival Jorge Lorenzo was their future and ended up at Ducati, this time losing with them, instead of losing against them. Worst of all, he was innocently involved in the death of his best friend Marco Simoncelli. Surely, this was the beginning of the end, of the slide into retirement?

Not at all. Last year Rossi made his second comeback and now he’s back where he was after his first comeback, leading the World Championship. Not even Jesus managed two comebacks, that’s why his story is so far-fetched.

At 313 Grands Prix, 109 wins and 197 podiums, Rossi’s career does defy reality. For very nearly two decades (I write this 19 years to the day since he made his GP debut on March 31 1996) he has stayed in one piece and stayed competitive. Most remarkable of all he still wants to do it: put his life on the line every other weekend every summer, even though he’s as about far from bankrupt as it’s possible to be.

Kevin Schwantz – a prototype Rossi if ever there was one – knows what keeps the 36-year-old racing. “Valentino is absolutely addicted to racing – if you told him he couldn’t race next year he’d go stark raving mad!”

Of course, Rossi is an addict for two good reasons: he loves racing and he still finds a joy in everything about the sport, from bumping and barging at the final corner to jetting around the world with his best mate from school.

But there’s nothing he loves more than a last-lap fight. Rossi lives for the battle, he doesn’t live for grinding out winning lap times in glorious isolation. Sunday’s Qatar GP was his kind of racing – diving up the inside, front tyre skating on the edge of oblivion, then squeezing himself under the bubble on the run to the line, fervently praying that Andrea Dovizioso’s Ducati wouldn’t motor past before the flag.

That’s another reason to believe that he has a serious chance of taking this year’s MotoGP crown. Qatar isn’t always a good indicator of how the racing will be for the rest of the championship (unusual track, unique conditions) but there’s plenty of other evidence that suggests this season will be tighter than most, with more last-lap sort-outs, which will suit Rossi’s inner warrior just fine.

It will also make a fitting final sequence to Rossi: The Movie, as he swoops through the final corner at Valencia to claim a 10th crown and move one title ahead of the late, great Mike Hailwood, the other rider most often considered for the title ‘Greatest of all Time’.

But don’t get too excited just yet. Marc Márquez will be back. And probably very soon.