Tony Adams thinks that Portsmouth are capable of surprising Manchester United and winning at Old Trafford in the FA Cup sixth-round tie on Saturday, claiming that the South Coast club's first-choice side are as good as any in the Barclays Premier League. His bold assertion is sure to raise eyebrows, but the Portsmouth assistant manager says that it is borne out by statistics.

“Our starting XI is probably as good as anybody in the League,” Adams said. “With the XI we've got, which is a very good XI, we're right up there with the clean sheets and the stats. I think we're fourth best in the League, which is better than Arsenal, so maybe Arsène [Wenger, their manager] should give us a call. There's nothing stopping us. Those XI on their day can do a job for us, I'm sure.”

Adams said that he has been encouraged to believe that Portsmouth can knock United out of the FA Cup by the numerous upsets that have occurred already this season, such as Coventry City's victory at Old Trafford in the third round of the Carling Cup in September. “For a one-off game like this, who knows?” Adams said. “On our day we've gone to some tough places and won. We've gone to the likes of Villa and won and we've had six away victories - something which is unheard of at Portsmouth. So there's nothing stopping us.

“You couldn't have foreseen Barnsley going to Liverpool and turning them over, and if Barnsley were in the Premier League, they'd probably be in Derby's situation or below. I think that's the beauty of a cup competition - you never know.”

For Adams, the competition stirs memories of success, but also of humiliation. In 1992, Arsenal, who were champions at the time, were knocked out of the FA Cup by Wrexham, who finished bottom of the Football League the season before.

“I remember when we [Arsenal] went to Wrexham and got knocked out of the third round and then the next year we went and won it,” the former Arsenal centre half told The News in Portsmouth. “The year before the Wrexham defeat we got to a semi-final, so you never know if it's your year or if it's not your year.

“You just go out there, you play your game, you try to be tough to beat and know your basic stuff - that's what you've got to do. You go back to the fundamentals of playing football. Simplistically, it's about stopping them scoring, being resilient, being tough to beat and then maybe get one up the other end, and then you're in the next round.”

Adams, who captained Arsenal to three FA Cup wins, insisted that Portsmouth could banish memories of their 2-0 Premier League defeat by Manchester United at Old Trafford in January, when Cristiano Ronaldo scored twice in the first 13 minutes.

Portsmouth have been in a rich vein of form since the arrivals during the January transfer window of Lassana Diarra, Jermain Defoe, Milan Baros and Lucien Aubey, despite Sunday's 3-1 defeat by Everton at Goodison Park.

David Nugent, the out-of-favour England-capped forward, is being monitored by Stoke City after a possible move to Ipswich Town fell through. Ipswich and Portsmouth had agreed a loan deal, but Jim Magilton, the Ipswich manager, lost interest in Nugent after the player admitted that he would not be fit for next week. The 22-year-old said that he needed extra time to recover from groin surgery.

Magilton said: “We have waited long enough. We were going to give him until the end of this week but the player has been honest enough to say he won't be fit and so we move on. Games are running out for us now and we have decided we need to move on and look at other targets.”

Nugent has struggled to hold down a place in the Portsmouth team since arriving from Preston North End last summer in a £6 million deal. Nugent, who scored 17 goals for Preston last season in the Coca-Cola Championship, has found the net only three times for Portsmouth.

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