The Old Trafford clock showed 55 minutes had gone when Freddie Ljungberg’a shot was spilled by Fabien Barthez. The first player to react was Sylvain Wiltord, Arsenal’s then record signing, to slot the ball home with minimum fuss to put Arsenal 1-0 up and ultimately wrap up the Premier League title. It was a great moment in Arsenal’s history, to win the title in their rival’s backyard and a moment Arsene Wenger described as the “shift of power” from the North to the South and from Ferguson’s United to his Arsenal.

However, it didn’t quite work out like that. The following season, despite leading the table for the majority of the season, Arsenal capitulated under the relentless pressure of the United juggernaut. A Martin Keown own-goal in the last minute away at Bolton, after Arsenal had lead 2-0, saw another power shift, this time in the title race, and it was United who went on to win the title.

The 2003/2004 season, along with “that night at Anfield” in 1989, is arguably the club’s defining moment. With Patrick Vieira, Robert Pires and Thierry Henry all in the prime of their careers, Wenger’s team went the whole season unbeaten and again it seemed that, for the third year running, the power had shifted. Back to London, back to Arsenal. Yet somewhere, somehow, that power was lost. Wrestled, or if you like bought, from Arsenal’s grasp by their west London rivals Chelsea and their Russian billionaire owner, Roman Abramovich.

Since the ‘Invincibles’ campaign Arsenal lost their way. Yes, they won the F.A. Cup on penalties in 2005, reached the Champions League final in 2006 and for a while last season, looked on course to win the title. But things haven’t been right, they haven’t been the Arsenal we have known since Arsene Wenger arrived at the club.

Lost in transition, out with the old and in with the new. Established international stars were replaced by raw and precocious youth. At times it looked a doomed project, one that while admirable in its intentions seemed over-ambitious in reality. During the period since Arsenal last won the league, both Wenger and the Arsenal fans have had to watch on as United and Chelsea have spared against each other to not only be crowned the best in England but, as in last year’s Champions League final, the best in Europe.

Wenger and the Arsenal faithful will have taken comfort in United’s victory in Moscow last year. The European Cup is the one gaping whole in the Frenchman’s CV and the club’s trophy cabinet. To think that new-money Chelsea, and perhaps more importantly, Avram Grant would take home the most prestigious trophy in club football before them was unthinkable.

Last year’s spirited campaign gave great hope for this season but the losses of Mathieu Flamini, Gilberto Silva and Alex Hleb rocked the boat and by the time Arsenal had recovered, the title seemed beyond their reach. Wenger has to take responsibility for this because it was his decision not to replace Flamini last summer and instead look in-house for his replacement.

Inconsistency ruled in the first half of the season and regulars at the Emirates were starting to think that maybe it was time for a change. But the inspired purchase of Andrei Arshavin, the return to fitness of key players and the emergence of Alex Song as a genuine defensive midfielder has seen Arsenal blossom as spring approached.

They are now unbeaten in 20 Premier League games and confidence is at its highest for a long, long time. Like junkies who wont admit to their problems, it seems Arsenal had to hit rock bottom to be able to rise to the top once again. Out of their regular starting 11 only Manuel Almunia and William Gallas are the wrong side of 30 and only Kolo Toure and Andrei Arshavin older than 27. Captain Cesc Fabregas is still only 21 and when he looks around him to see what this team are achieving at such a young age it should inspire him to stay at the club for a long time.

If Wenger is looking to shift the power back in Arsenal’s favour, then tonight is as good a night as any to start that process. The potential in this young Arsenal team is frightening and it is probably better equipped than any other during Wenger’s reign to be able to keep that power if they can wrestle it from United’s hands.

It won’t be easy though because despite their recent wobble, United are still a formidable side. One that not only has the combination of youth and experience but also one brimming with quality and character, as they have shown in the recent comebacks against Aston Villa and Tottenham.

Arsenal start tonight’s game with a makeshift defence and one that looked extremely vulnerable away at Liverpool last week and you feel that not conceding will be their biggest problem. However all great dynasties start with one definitive act and with this game coming one week shy of 7 years since Wiltord’s goal saw the first shift in power, what better occasion than tonight to start to re-address the balance.