Portsmouth - 2 Manchester United - 0: Alex Ferguson knows where to worry first. In this result his eye will fall not on the goals that a capable Portsmouth scored but on the ones that Manchester United failed to register.

Chelsea, Everton and Birmingham City had already kept clean sheets against them and the side are only 11 games into their Premiership programme.

Prospects are being damaged and so, too, is pride at an institution so famed for its uninhibited attacking. The feeling of helplessness is all the more acute because United have a battery of creative attackers who should make goals an inevitability.

The side seem sure to cut loose sooner or later, but by then they may have been cut adrift entirely from Arsenal and Chelsea in the table. A dozen clubs have more Premiership goals to their name than United's humble total of 11.

Portsmouth's defence is largely composed of free transfer signings, yet they eventually established total mastery of the visitors. United, bright at the start, were a discouraged side well before the close.

Soon after falling behind, they might have equalised, but Cristiano Ronaldo headed Gary Neville's cross against a post and Alan Smith, barging in to force the rebound over the line, somehow sent it over the bar instead.

Despite a zestful opening, United never dismantled the Portsmouth back four and Shaka Hislop's saves did not need to be spectacular.

It will rankle with Ferguson that Paul Scholes should steer one pass from Ryan Giggs negligently close to the goalkeeper when he might have had the opener, but that lapse is part of a wider concern. Scholes performed well enough, but United need him to be a supreme, game-changing talent again.

United's problem is in the centre of the pitch. Perhaps unsure of the right combination, Ferguson even started with Phil Neville there rather than the captain Roy Keane.

With no one to set the rhythm and knit the play together, United have a disconnected if enviable set of talents on the pitch.

Wayne Rooney, like many others, began promisingly, but the most emphatic message he inadvertently sent out was that he really is just a teenager whose emotions are yet to be governed.

He was booked for a foul shortly before the interval, although Nigel Quashie should have been dismissed for retaliation even though his swinging arm missed its target.

If United enjoyed favourable refereeing decisions against Arsenal, there was no assistance from Neale Barry here.

As the game slipped away, Rooney was at risk of a second caution. The youngster was more intent on getting mad than helping his side get even.

Ferguson will now ask the FA to consider the video of an incident from the Arsenal match in which Thierry Henry's knee catches Gabriel Heinze on the head.

It has taken the Old Trafford club a week to complain and the referee Mike Riley, who saw the incident last Sunday, believed the contact to be accidental.

The manager, provoked by Arsenal's squeals of complaint, appears bent on harassing the Highbury club, but he is finding it hard to apply a more satisfying sort of pressure.

United are nine points behind both Arsene Wenger's side and Chelsea, praying for the unlikely decline of both.

Amdy Faye, the Portsmouth midfielder, wondered if the visitors had exhausted all their motivation against Arsenal. Whatever the reason, the Fratton Park team had the strength, skill and pace on the break to beat United.

They took the lead with David Unsworth's 53rd-minute penalty after Rio Ferdinand had given Aiyegbeni Yakubu's shirt an insufficiently sly tug.

The Nigerian himself scored 19 minutes later, turning Mikael Silvestre and then finishing with a shot that took a small, helpful deflection off the Frenchman.

Following Patrik Berger's groin strain, Harry Redknapp presented the highly-effective 20-year-old Valery Mezague with his English Premiership debut.

According to Redknapp, Mezague would then have moved to Tottenham for £4 million had he not suffered serious injuries in a car crash. Later, while visiting Portsmouth to discuss the present loan deal from Montpellier, the youngster's agent was at the wheel and drove them straight into an oncoming vehicle. No one was hurt.

There tends to be something unconventional and even faintly whimsical about Redknapp's side, but, with successive defeats at Fratton Park, United know just how practical Portsmouth truly are.

Ferguson admitted the defeat was "a real kick in the teeth. It absolutely destroys what happened last week against Arsenal. It is a terrible disappointment, just not good enough. We missed an incredible number of chances and it was just not good enough really.

"For the quality we've got we should be doing better in these games, but it is certainly not an easy place to play, especially when you are one down.