Paul Scholes scored twice as holders Manchester United [Images] cruised effortlessly into the FA Cup semi-finals with a 4-0 victory at Southampton on Saturday.

United, showing no ill-effects from their Champions League exit at AC Milan in midweek, took the lead after only 90 seconds through captain Roy Keane and never looked back.

Portugal winger Cristiano Ronaldo [Images] struck just before halftime, and former England [Images] midfielder Scholes added a third three minutes after the interval before completing the rout with a late header.

Southampton, who face a battle to avoid relegation from the Premier League, never threw in the towel at St Mary's but never seriously threatened Alex Ferguson's men.

United, eight points behind league leaders Chelsea, could certainly not have hoped for a better start after their miserable trip to Italy [Images].

They won a corner from which Keane twisted round sharply to score with a deflected shot off Southampton striker Peter Crouch.

Southampton coped well with the setback and their Swedish midfielder Anders Svensson forced a near-post save from American keeper Tim Howard with a vicious angled shot and screwed another effort wide from the edge of the area.

The momentum was all with the Cup holders, however, who made light of the injury absence of winger Ryan Giggs.

ROONEY CHANCES

It should have been 2-0 on 23 minutes when keeper Paul Smith tipped Wayne Rooney's [Images] fierce shot on to the crossbar, and the England teenager followed up the rebound with a header from point-blank range that somehow flew wide.

Smith, keeping fit-again Antti Niemi on the bench, pulled off a brilliant save to deny Rooney again two minutes before the break, pushing the striker's fierce shot on to the post.

There was nothing the Saints keeper could do, however, on the stroke of halftime when Rooney made a surging run into the box and laid the ball back for Ruud van Nistelrooy [Images], who picked out Ronaldo for a crisp finish into the corner of the net.

That goal effectively killed the game as a contest.

Southampton were on the back foot within minutes of the re-start and Scholes pounced when Smith parried a Van Nistelrooy effort and the United playmaker steered the ball into an unguarded net.

The goal led to a brief interruption after a red flare was thrown on to the pitch from seats behind Smith's goal housing visiting fans.

Southampton, who memorably beat United 1-0 in the 1976 FA Cup final, nearly snatched a consolation goal through striker Henri Camara but Scholes was on hand to turn victory into a rout with a far-post header after a fine cross from Van Nistelrooy.

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