Lunch with one of the world’s most talented and complicated sportsmen is at Roka, a sleek Japanese-fusion restaurant packed with chattering expense-account lunchers in London’s Canary Wharf. Ronnie O’Sullivan, current and five-time world snooker champion, has eaten here a couple of times before. “It’s a local for me and the food’s really nice,” the 37-year-old explains in a softly spoken Essex accent. He peers with interest at a dish with an open-shell tiger prawn that is being carried to a nearby table.

O’Sullivan, nicknamed “Rocket” for the exhilarating speed at which he can clear the balls on a snooker table, is for many the most talented player in the game’s history. Who else could win, as he did in May, its most prestigious tournament, the world championship in Sheffield, despite not having played professional snooker for the previous 12 months? Imagine Roger Federer taking a year off then popping back to win Wimbledon.

Like many, I am a casual snooker follower but a big Ronnie fan: he is the game’s last big draw, a throwback to the characterful days when it attracted as many as 18m television viewers to watch players like Alex “Hurricane” Higgins and Jimmy “the Whirlwind” White. But I approach our lunch with caution. My guest has a well-deserved reputation for controversy. At times he has seemed to hate the game he has been fated to play so superlatively.