HOWZAT

Quinn admitted that he had attempted to persuade Keane to remain at the club but realised he was fighting a losing battle.

"Roy, as he says himself, is his harshest critic. He just felt he had completed his journey here, and he just felt he didn't want to get it unstuck any further and find ourselves in deeper, darker territory.

"That's the measure of the guy. It's funny, in situations like this, I am sure nine times out of ten, the chairman is saying how the manager was trying to keep his job. It was the other way round.

"It's a disappointing day in many respects, but of course, we fully respect his decision.

"And of course, once he made his decision, I said to him, 'I know you too well, Roy, to try to overturn it now' once he went over that line."

Keane had been been due to attend a press conference at 1pm today but the manager and club had already reached breaking point after a morning of talks.

In a brief statement, Keane thanked his staff for their support.

"I would like to thank my staff, players, Niall Quinn and in particular the fans for their support during my time at Sunderland, and I would like to wish the club every success in the future," he said.

Disquiet had grown on Wearside over the past few weeks as results went the wrong way and Keane refused to sign an extension to the contract that was due to run out at the end of the season. Speculation heightened as Keane publicly questioned his ability to arrest his side's decline.

“I ask myself every single day if I am the right man for Sunderland," Keane said after his team's 4-1 defeat to Bolton on Saturday.

"I asked myself this morning and I said that I was. Tomorrow morning if the answer’s no we will have to look at it.

“I have to be honest in my assessment. It’s not about what’s best for Roy Keane. It’s Sunderland Football Club. I might wake up on Monday morning and think I’m the right man. On Tuesday it might be different.”

Last month, local radio reports said that Keane was on the verge of being sacked and bookmakers suspended betting on the possibility of the Irishman either being axed or walking out.

Keane, 37, was appointed manager in August 2006 and was given unprecedented financial backing by the club’s board. He led Sunderland into the Premier League in his first season in charge and finished 15th in his maiden Premier League campaign.

Keane spent more than £80 million bringing in the likes of Djibril Cisse, Anton Ferdinand, El-Hadji Diouf, Pascal Chimbonda and Steed Malbranque, but his new additions - questioned by many - have failed to gel and he leaves with the club in 18th position.