Wayne Rooney's gambling debts may have spiralled to a reported £700,000 (€1 million), but the young superstar today made what could yet turn out to be a priceless contribution to Manchester United's championship challenge.

After having a clear penalty claim turned down just before the break against Arsenal at Old Trafford, Rooney took matters into his own hands nine minutes after the re-start.

Taking down Mikael Silvestre's magnificent left-wing cross with one superb touch, Rooney blasted home his 17th goal of the season.

He was not finished there either — setting up Park Ji-sung for the late second which sealed a ninth successive Barclays Premiership win, maintained United's recent stranglehold over Arsenal in league combat and, most importantly of all, closed the gap on Chelsea to seven points.

With only five games of the campaign remaining, however, the odds are still stacked heavily in favour of Jose Mourinho's men.

But in making his bold claim on Friday that United would have a "real chance" if they beat the Gunners, Sir Alex Ferguson knows his side — who still have to visit Stamford Bridge — should edge even nearer to the defending champions by beating doomed Sunderland on home soil on Friday.

That would leave Chelsea to negotiate a potentially hazardous trip to Bolton the following day.

In front of 70,908 — the biggest crowd ever to see United play a game at Old Trafford, the two most successful sides of the Premiership era produced a thrilling spectacle.

Arsenal started brightly before United emerged from their shell. By half-time, though, the game was a thrilling spectacle of end-to-end attacks - with the moment of controversy every gripping encounter needs coming two minutes before the interval whistle went.

When he was informed on Friday that Graham Poll had been installed as referee in place of Phil Dowd, Ferguson declared himself satisfied on the basis England's World Cup official had the experience to handle such a big match.

Poll succeeded in keeping a lid on tempers. Unfortunately for United, though, when called upon to make the big decision he got it totally wrong.

The referee's only defence was that he was unsighted because, as TV replays showed, the incident itself was clear enough.

Kolo Toure, having fallen over a prone Jens Lehmann — who had already seen Rooney skip round him — flung both hands despairingly at the ball as it flashed goalwards.

It was a save Lehmann himself would have been proud of and seemed even to stun Philippe Senderos as the shot crashed back off the post he had rushed back to defend.

Much has been made of Rooney's temperament — as well as his gambling debts — but under the circumstances, the United man did well to limit his protests to just a fierce exchange of views with Poll.

Lehmann did well to prevent the outstanding Ronaldo netting another in stoppage time.

But the German could not alter a result which, while keeping the title race alive over Easter, does not do much for Arsenal's hopes of a top-four finish.