Ronnie O'Sullivan, the defending champion, has withdrawn from the UK Championship in Bournemouth because of "physical and nervous exhaustion."

O'Sullivan, 23 next month, has been showing signs of depression for more than a year and his appetite for practice has diminished greatly. He has met his commitments but even though he won the Scottish Masters in September he has talked of retirement.

He complained then that he had fallen out of love with the game, saying: "If I never saw a snooker table again it wouldn't bother me. I hate the game. I'm just in it really for the money."

Even just a few days before the UK Championship started O'Sullivan was still a troubled young man. Asked to predict the score of his first-round match, O'Sullivan said his opponent John Read - who now gets a wal-over - would win 90 or 9-1.

He has been happiest while fishing in the peace and quiet of Stamford, Lincolnshire, with his best friend Del Hill, who has travelled with him on the circuit to keep his spirits up.

O'Sullivan, whose father is serving a life prison sentence, was devastated three years ago when his mother was also briefly imprisoned for VAT offences. A relationship with the mother of his daughter also ended in acrimony.

O'Sullivan has had a roller-coaster professional career. At the 1996 world championship he assaulted press officer Mike Ganley for which he was fined £20,000 and given a suspended two-year ban.

O'Sullivan failed a drug test at the Irish Masters in March and had to forfeit the title and his £61,000 first prize. He learnt of the positive test while playing in the World Championship and he faded badly in his semi-final against John Higgins.

Yesterday his manager Ian Doyle said: "His doctor has ordered a complete rest. I would hope that people in snooker will rally round Ronnie just as the people in football have rallied round Paul Merson and Paul Gascoigne.

"His situation will be reviewed in four weeks but he may take longer to get right."

Meanwhile, Ken Doherty became the first player to move into round three when he whitewashed Scot John Lardner 9-0.

UK Championship (Bournemouth) - First round: K Doherty (Rep of Ire) bt J Lardner (Sco) 9-0. Second round: M Holt (Eng) bt G Dott (Sco) 9-1, M Williams (Wal) bt D Dale (Wal) 9-4.