He has a sense of inner calm that is rarely disturbed. Until, that is, Ferguson rides into town. Ferguson, you see, makes Wenger feel uneasy too.

It's not a matter of mutual dislike, but mutual respect. Both know they are capable of losing to the other.

The urbane Frenchman and the intense Scotsman have little in common apart from the fact that they are the most successful managers in the Premiership.

In his 14 years in charge at Old Trafford, Ferguson has faced no shrewder opponent than Wenger.

His countryman George Graham is the one possible exception and it was the competitive nature of their rivalry that set the tone for the turbulent series of matches between the clubs in recent years.

Wenger inherited an outstanding Arsenal squad, added stealth and Gallic flair and was rewarded with the Premiership and FA Cup double in his second season.

Championship runners-up for the past two seasons, Arsenal are probably the only realistic challengers to United's domination.

That is why the United manager paid Wenger the ultimate compliment in Holland the other night when he rested so many of his star names from the Champions League encounter with PSV Eindhoven.

At kick-off time, Dennis Irwin, David Beckham, Ryan Giggs, Ronny Johnsen, Teddy Sheringham and Andy Cole were all missing from a team that was already without the injured pair of Fabien Barthez and Jaap Stam.

This was not intended to belittle the PSV challenge in any way but, by the end, Ferguson was justifying a 3-1 defeat with words that will have brought a smile to Wenger's face.

'Tonight has been more about Arsenal than the Champions League,' he said.

This may have been difficult for PSV and their fans to understand. The Champions League is, after all, the premier prize in European football.

But, in the high-octane world of the English Premiership, no fixture stirs the blood, excites the TV producers or has greater relevance to the outcome of the title race than Sunday's clash at Highbury.

The fact that Beckham, Giggs, Irwin, Johnsen, Sheringham and Cole are all likely to play along with Barthez, now recovered from injury, reveals all we need to know about Ferguson's priorities at this stage of the campaign.

Last season United won 2-1 at Highbury, picking up just three of the 18 points that eventually separated them from Arsenal at the top of the Premiership.

A win on Sunday would give them a six-point lead over their great rivals - a significant advantage at this stage of the season. Defeat, though, would be psychologically damaging to United and bring into question the system of rotating players with the idea of resting them before big matches.

Wenger and Ferguson follow the same policy but, as in all things to do with football, victory hides a multitude of sins while defeat always needs an explanation.

As Ferguson sought to justify his disastrous team changes in the aftermath of the PSV defeat, the same rotation system helped produce a truly impressive 2-0 Champions League win for Arsenal over Lazio. Or did it?

Wenger started the season by playing two strikers - Thierry Henry and Nwankwo Kanu - and resting two.

But Henry, Kanu, Dennis Bergkamp and Sylvain Wiltord have all featured significantly in Arsenal's past four matches, with all four on the pitch at the same time in some games.

So, after the Lazio victory, Arsenal will be in buoyant mood, though if there is any substance to the rotation theory their four strikers should all be exhausted.

United may not be quite so bullish mentally but, having just had a good rest, they should all be as fit as butchers' dogs. Ferguson has never been guilty of turning a little drama into a major crisis and I suspect that the six goals conceded in two games against Chelsea and PSV will be seen in the fullness of time as no more than a blip.

This time last season, United stumbled at Old Trafford against Wimbledon (1-1) and Southampton (3-3) and then lost the plot completely at Chelsea (0-5).