Two years ago at the age of thirteen years, four months and 26 days, Norwegian chess sensation Magnus Carlsen became the youngest chess grandmaster in the world. This piece is not about Carlsen -- all will be revealed.

In a world where being at the top of your profession is measured by the number of zeros (in the bank account), it’s reassuring to know that there is one former star out there whose talent is so special that an infinite number of zeros would not do justice to that talent. I present Simen Agdestein as my candidate for greatest sportsman ever.

I admit I have a vested interest in my choice of all-time hero: I play chess (badly) in the Third Division of the London League and regularly get thrashed by average players who delight in "skinning the rabbit". And even at my very average club level, I know how many hundreds of hours I have studied opening and endgame theory to make it to the Third Division of the London League.

I also play a bit of Sunday morning football, again, at a level that people with a physical and visual impairment may feel is not beyond their capabilities. But if I need a modicum of ability to play these sports at a competitive level, (How wonderful I feel if I beat a chess opponent ranked higher than me, or set up our taxi driver striker with a perfect through-ball), what talent does Agdestein have to be able to play at the pinnacle of each sport? It is simply beyond belief.

You can ‘Google’ Agdestein to get the facts and figures of a remarkable career, or to be more precise, two remarkable careers.

It might be enough for some people to represent their country at football, and by all accounts, Agdestein was a very good centre back (possibly the best in Norway’s history). But it wasn’t enough for him to be a star at home and abroad (he also played for Aberdeen in the Scottish league). He had much more talent to unfold as a chess grandmaster, certainly the greatest in Norwegian chess history and at one time, one of the world's top players.

It is not unusual for footballers to have talents in other areas: Diego Maradona was a highly proficient cocaine addict; Paul Gascoigne could ingest 10 pints and two kebabs before participating in brawls; Paul Merson managed to combine the above two and more: he could also gamble at the highest level. So it is quite reassuring to know that our hero Simen liked nothing more after a gruelling game of football in the Norwegian league than going over Bobby Fischer’s 60 memorable games to enhance his opening repertoire. Not for him the bars and clubs of Sleazeville where drink flows and papparazzi cameras capture the nuances of the evening. For night out read: knight out to (square f6), for porn read pawn, and for three mates read mate in two.

It’s not astonishing that Agdestein played football for Norway, nor that he is a chess grandmaster. It is more than astonishing that he achieved both, and indeed for some time kept the two careers going until an injury forced him to retire from football. Surely there can be no sportsman in history who has achieved greatness in two such different sports and played at a level in each sport that most of us can only dream about.

So where is Agdestein’s link with Carlsen at the beginning of this story? He is Carlsen's chess coach. I look up to Agdestein along with other aspiring chess players at the Norwegian School of Sporting Excellence. Agdestein even wrote a book about his prodigy: Wonderboy: How Magnus Carlsen Became the Youngest Chess Grandmaster in the World. A slightly more appealing volume than those ghosted books filled with details on the number of women a striker has bedded and how many pints of lager he could down in an evening.

And just to make sure he doesn’t become too bored, Simen is now pursuing a third talent, ballroom dancing -- whatever next.