George Best was last night recovering in intensive care after undergoing a "last chance" liver transplant at London's Cromwell Hospital.
He had been on a waiting list for nine months and was called yesterday at 6 a.m. for the procedure.
A hospital spokesman, Prof Roger Williams, said the operation had been completed well within the normal 16-hour timescale and, although cautious, he indicated that the procedure, which began just after 10 a.m. yesterday, had gone well.
He also said Best was now much better than he had been and that the outlook was positive. That, however, depends on the former Manchester United star's recovery rate over the coming week. Medical staff will continue to work to ensure his body does not reject the new organ. Prof Williams added that the chief surgeon treating Best, Mr Nigel Heaton, had completed "some extraordinary surgery".
At around 7.30 p.m. last night Mr Heaton, the consultant surgeon, and Prof Williams, Best's consultant physician, said in a statement that the operation had proceeded satisfactorily.
"After some initial worries, his condition has substantially improved," they said.
Recently returned from a holiday with his wife, Alex Pursey, in Malta, Best (56) has been sober for at least 12 months, thus allowing doctors to consider him for the transplant. He had been warned that, following decades of abuse, one more drink could kill him.
It is understood he had decided against private treatment and opted to take his place on the National Health Service waiting list, thus avoiding "queue-jumping".
Liver transplants are now regarded as routine but remain complex operations. Liver disease kills some 5,000 per year in the UK and the waiting list for transplants stands at about 150. Best has been told he should be sitting up in bed within three days of successful surgery, and home within two or three weeks. Prof Williams has said he should be "restored to good health" within a year.
Last December Best was told he needed a transplant following medical confirmation that his liver was only functioning at 20 per cent. Prof Williams, Director of the Institute of Hepatology at University College London, who had been treating Best, said then that the conditions were right for the operation to go ahead.
Best was treated at the Cromwell Hospital two years ago for serious liver damage.
In 1984 he was arrested for drink-driving and assaulting a police officer. There was further controversy in 1990 when he appeared drunk on the BBC chat show Wogan. Best later said BBC staff made drink available to him before the live TV show.
Best married his second wife seven years ago and moved back to the North in an attempt to find a quieter lifestyle away from the glamorous surroundings of his drinking days in the 70s.
The North's Sports Minister, Mr Michael McGimpsey, sent his best wishes to Best and his wife and son Callum from his first marriage, who was also seen at the hospital yesterday. The Ulster Unionist Minister said: "Our thoughts are with George and Alex and his family right now. I hope and pray the operation is a success and that we can once again see George in good health."
A spokesman for the Irish Football Association also sent his best wishes.