United lead the Barclays Premiership by six points, are in the last 16 of the Champions League and, after picking up a home tie against Portsmouth in the FA Cup fourth-round draw yesterday, the United manager called for a repeat of 1999’s heroics. “We must have a go at it [the treble],” he said. “There is no point in being negative, let’s enjoy it.” If United do go the whole way, Larsson is likely to be along for the ride.

After Sten-Inge Fredin, the Helsingborgs chairman, revealed yesterday that the Swedish club would not stand in Larsson’s way if the forward wanted to stay at Old Trafford, United are understood to be preparing to request that the loan be extended until the end of the season.

Any agreement would be dependent on Larsson’s approval, but United are thought to be confident that the Swede, who scored on his debut in the 2-1 FA Cup third-round win at home to Aston Villa on Sunday, will want to stay beyond March 12.

Ferguson was banking on Larsson remaining at United until at least the end of the season when Helsingborgs first agreed to a short-term loan towards the end of November, but, mindful of the Swedes’ generosity, United were wary of antagonising a club with whom they enjoy excellent relations by jumping the gun and demanding an immediate extension.

United are reputed to have paid a loan fee of £800,000 — split between player and club — but the Premiership leaders would be required to pay significantly more in compensation if Larsson chooses to miss the start of the Swedish season in favour of remaining at Old Trafford.

“It is very early days, nothing has been done, but if Henrik decides he would like to stay beyond March, then obviously we would look at the situation and seek to reach an agreement with Helsingborgs sooner rather than later,” a United source told The Times.

Fredin’s comments were echoed by Stuart Baxter, the Helsingborgs coach. “The attraction of Manchester United was a short-term deal,” Baxter said. “If that has changed where an extension would mean extra finance for the club, that’s nice, but we have still got to try to make a team.

“We knew the situation might happen when we did the deal. It is Manchester United, after all, not Bristol Rovers.”

With Larsson making an immediate impact, and Louis Saha expected to return to training this week, Ferguson admitted that he has his sights set on a repeat of the 1998-99 season, when United became the first club to win a treble of Premiership, FA Cup and Champions League.

With Chelsea six points behind in the league, Ports-mouth up next in the FA Cup and unfancied Lille to come in Europe, Ferguson is keen to push home his advantage. “I am sure our present position will drive us on even more,” he said. “We are here for the long haul, plus we have youth and strength on our side.”

Of more immediate concern than Larsson’s situation is that of Owen Hargreaves. There is a general consensus at Old Trafford that a deal is unlikely to be struck until the summer, not only because of Bayern Munich’s prohibitive asking price of £21 million, but also because Ferguson may harbour concerns about paying such a huge amount of money for a player who has yet to recover from a broken leg.

Hargreaves was initially expected to feature against Borus-sia Dortmund on January 26, when the Bundesliga season resumes after its winter break, but his comeback has been put on hold until next month. Ferguson is keen to ensure that the England midfield player regains full fitness before breaking the bank to sign him.

Meanwhile, Alan Smith is likely to spurn any offers to leave United, despite virtually every Premiership club, with the exception of Arsenal, Chelsea, Liverpool and Manchester City, inquiring about signing the forward.