FOR the second week in succession, Manchester United turned on the style to leave top-four Premiership opponents gasping. After Bolton found themselves on the wrong end of a Red Devils super show last week, this time it was fourth-placed Portsmouth's turn to feel the power.

Louis Saha's penalty and a brutal Cristiano Ronaldo free-kick put the hosts two up inside the opening 10 minutes, and a Vidic header from a corner helped celebrate Alex Ferguson 20th anniversary in the Manchester United job in real style.

Portsmouth's hopes of spoiling Alex Ferguson's party were dealt a huge blow when Sol Campbell was forced to pull out with a virus.

Andy O'Brien stepped in for the first time this season, charged with the task of quelling the power of Wayne Rooney and Louis Saha in a United line-up unchanged from the one that thumped four past Bolton last weekend.

There was no prematch presentation for Ferguson and he would have been pleased with his side's start too as they went in front after just two minutes.

A sleeping Pompey defence was caught napping by Gary Neville's quick throw to Wayne Rooney, who had burst unmarked into the area. Dejan Stefanovic got back to make the tackle but succeeded only in upending the United man from behind and Louis Saha scores from the penalty spot.

The visitors, so effective defensively this season, were struggling to contain a United side fizzing passes about on a greasy pitch. O'Brien left Saha in agony with a studs-first challenge but after the Frenchman limped away, Ronaldo stepped up to fire a sensational 30-yard free-kick into the corner of David James' net. United were almost in again shortly afterwards when Stefanovic denied Giggs with a challenge and James pulled off an excellent low save to deny Neville's left-footed shot. On a day of nostalgia, Ferguson received a blast from the past when former United favourite Andy Cole replaced Manuel Fernandes at the interval.

Portsmouth had the first shot of the second period as Benjani Mwaruwari brought a smart low save out of Van der Sar. James then denied Vidic a certain goal from a corner. Portsmouth were more of a danger in this half and Nico Kranjcar wasted a glorious chance to pull one back when he thrashed wildly at the loose ball when Ferdinand's block fell to his feet and saw his shot fly well wide.

But United were on top and a third goal seemed inevitable, although Pompey boss Harry Redknapp would have been disappointed when it arrived after 65 minutes as Vidic rose unopposed to power home Neville's curling cross to give Ferguson his win.