Steve Davis today warned snooker's elite not to write off troubled star Ronnie O'Sullivan for this year's World Championships in Sheffield. O'Sullivan has won just one ranking tournament in the last four years and was at the centre of a bizarre incident at a press conference after defeat at last month's Beijing Open.

The 32-year-old made lewd comments after being questioned by local journalists, prompting some to question whether he has the mental strength to rediscover his best form.

But six- time world champion Davis claims talk of O'Sullivan's demise is premature as the world's top players prepare for the 17-day marathon, starting on Saturday at the Crucible.

"On his day, Ronnie is virtually unstoppable and even his average performance is excellent," said Davis. "All the analysis of his defeats are always aimed at him but that is unfair on the rest of the field.

"Players like Stephen Maguire, Mark Selby and John Higgins are capable of beating him because they are all excellent in their own right. Ronnie is favourite to win again and the other players know what he is capable of - he has dominated the Snooker Premier League, winning it four years in a row.

"He has Liu Chuang [of China] in his first round match at the Crucible and despite what has happened, if he is on form, he is still the man to beat."

Gone are the days when the stars of Davis, O'Sullivan and Stephen Hendry dominated all the top events.

There is a changing of the guard at the top of the game with the older players giving way to younger talent, making it harder for O'Sullivan's brilliant but inconsistent style to win through.

"You have to be so consistent to reach a level of winning on a regular basis now," said Davis.

"This tournament is wide open and has got more so in recent years. The best players over the last six or seven years face a real fight from the new generation who are coming of age."

At 50, Davis has little expectation of reaching the latter stages of snooker's premier event, but he insists his levels of preparation are the same as when winning six titles in the 1980s.

"It's the ultimate tournament and one every player hopes to perform your best in," said Davis, who is an official spokesman for matchroombets.com.

"I don't think I approach the tournament any differently to when I was favourite for events like this.

"I never went into it expecting to do well - I just hoped to perform when it matters and that is still the case.

"I have Stuart Bingham in the first round and the bookies have him as favourite. But I am looking forward to it and let's see where it takes me."