Merciless United make Keane pay and claim top spot

His rookie side were ruthlessly exposed and humiliated on home territory by his former team, Manchester United.

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Louis Saha scored two, taking his season's tally to four — three of them against hapless Sunderland — and Wayne Rooney scored his first for two months as he tortured the home defence with his movement.

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But it was Cristiano Ronaldo who guided the champions to their easiest win of the season.

The Portugal winger scored one to take his tally to 17 goals, including a dozen in the Barclays Premier League. United manager Sir Alex Ferguson could even afford to rest him for the final half-hour and preserve the legs which have now scored 15 of those goals in the last 13 games.

Keane predicted his former team are on course to retain their title. He said: 'My money is still on United and that hasn't wavered.

'They were missing players but could still flex their muscles. They beat us with class and quality. They're very good attacking-wise and their two centre halves are not bad either. To win the title you need a good combination.'

The Sunderland boss, who found time to wave to and acknowledge the surprisingly small number of travelling supporters, knows he is now deep in a relegation battle.

As he prepares to face Bolton at home on Saturday, he said: 'We're in a sticky patch. It's a massive battle. The easiest thing for the fans would be to get on the players' backs — but they haven't done that.

'The best side will win the league and the worst three will go down, but I believe we aren't one of them. We do have to back it up with a few results, though.'

The inevitable opener came in a swift, 20th-minute move which exposed Sunderland's fragile defence. Danny Higginbotham, one of six former Old Trafford men in the Sunderland 16, played Rooney onside as the England striker met Wes Brown's pass from a neat onetwo with Ronaldo. Craig Gordon had no chance once Rooney eyed his spot inside the post.

The home side were opened up again in the 30th minute when United turned a promising Sunderland free-kick into their second goal within seconds. Higginbotham and Paul McShane were still sprinting back from a poor Danny Collins pass when Ronaldo found Rooney on the right, the cross came in and Saha beat Collins to touch it past Gordon.

Keane handed a debut to 17-year-old South Shields-born striker Martyn Waghorn and the youngster put in a lively and enthusiastic shift, despite the unenviable task of being marked by Rio Ferdinand.

The decision to turn to a teenager who has made his mark with 10 goals for the academy side was a brave one, but the reality is that it is also another sorry reflection of the cash Keane has wasted in the transfer market. Anthony Stokes, David Connolly, Andrew Cole and Roy O'Donovan were all unable to earn the right to start and former Old Trafford midfielder Kieran Richardson only made the bench on his return from injury.

With the Sunderland midfield contained, Kenwyne Jones and Waghorn struggled to make any impact, with Jones, in particular, resorting to longrange efforts.

United were three ahead at the interval when Ronaldo scored with frightening accuracy after Dwight Yorke had pulled down Darren Fletcher near the edge of the area.

Ronaldo's free kick flew straight into the top left corner and Gordon did not move a muscle.

Keane could have made 11 changes at the break, but Wallace was the man sacrificed and Grant Leadbitter introduced as the manager made the overdue switch to a five-man midfield in a bid to shore up his team and prevent an embarrassing scoreline which could dent their goal difference further. It is now down to minus 21.

Leadbitter at least conjured a rare opening for Jones, who forced a good one-handed save from Tomasz Kuszczak but it was Keane's former team who looked more likely to score, even when Ronaldo departed to an ovation from the majority of the 47,360 crowd.

His replacement Ji-sung Park, back from a lengthy lay-off, instantly played in Nani but the Portugal winger's shot with the outside of his boot cleared Gordon's far post.

The increased volume by the home support in the last half-hour should have lifted Sunderland to at least score a consolation goal.

But although Kuszczak made two comfortable saves from Chopra, Richardson — whose arrival in place of Yorke was popular — predictably screwed one shot embarrassingly wide.

Instead, it fell to Saha to wrap up the scoring, hitting his second of the afternoon from the penalty spot following a clumsy Collins challenge from behind on Nani, who had raced on to Rooney's delightful flick.

Sunderland: Gordon, Whitehead, McShane, Higginbotham, Collins, Wallace, Etuhu, Yorke, Waghorn, Jones, Chopra. Subs: Ward, Richardson, Cole, Leadbitter, O'Donovan.

Man Utd: Kuszczak, O'Shea, Ferdinand, Vidic, Brown, Ronaldo, Fletcher, Carrick, Nani, Rooney, Saha. Subs: Heaton, Evra, Park, Pique, Tevez.

Referee: Uriah Rennie (S Yorkshire)