Sunderland 0 Wigan Athletic 3:Roy Keane will head into the transfer market once again this week knowing his Sunderland dream is in serious danger of turning into a nightmare.

The Wearsiders headed into the new season brimming with optimism after Keane inspired them to the Championship title. But half a season or so and €48 million on, they are engaged in a desperate fight for Premier League survival and confidence is rapidly dwindling.

On arriving back on the stage where he himself had performed for so long with such distinction, Keane insisted they were not there simply to make up the numbers.

But having seen his admittedly much-changed side dismantled by what was in large part Wigan's reserve team as they fell at the first FA Cup hurdle, the alarm bells must be ringing.

In the immediate aftermath of the game, the Sunderland boss admitted he was ashamed of a woefully substandard performance, and that was significant: Keane does not do shame, or regret, and it was clearly a painful experience for him.

Having managed to secure the return on loan of the Manchester United defender Jonny Evans until the end of the season - the youngster had a day to forget against Wigan - Keane will try to attract as many as four new signings to the Stadium of Light this week.

It is a task he knows will be made no easier by Saturday's display, but the Corkman remains defiant.

He said: "Listen, how many games have we lost this year? We have lost lots of games this year. I sound like an old record-player, but we have got to work harder, we have got to bring in one or two players and we keep persevering.

"You have to persevere in life. We have a tough game (against Portsmouth) next week. We gave players a chance on Saturday, we are chopping and changing, we are bringing players in.

"We brought Jonny back in and we will maybe have one or two for next week - but that is a big 'if'."

Keane, who has been linked with the likes of Celtic defender Bobo Balde, Reading duo Stephen Hunt and Leroy Lita, Blackburn's Robbie Savage and Derby's David Jones, while a decision on Quinton Fortune is expected this week, was without several key men through injury and suspension on Saturday, and the lack of depth in his squad was cruelly exposed.

Even so, Wigan defender Paul Scharner could scarcely believe his luck when he found himself unmarked as he headed home Josip Skoko's 19th-minute free-kick.

Sunderland were comically inept 11 minutes after the break when, in his effort to atone for Evans's dreadful back-pass, Paul McShane succeeded only in steering the ball into his own net.

Substitute David Cotterill did not need a helping hand to arrow home a third goal 14 minutes from time, and had Craig Gordon not turned Michael Brown's late effort against the post, Keane's fury might have reached new heights.

He said: "If we had been here until next week, we wouldn't have scored, which surprised me, because generally at home we have looked a threat. But we have to get back and focus on our league form; we do not have a choice.

"That's our bread and butter. We will get back to that and it is a tough game for us next week."