"The first time I remember seeing that group was the Youth Cup final, and all those kids were playing, " Strachan recalls. "Beckham, Scholes, and the Nevilles, I think [Ryan] Giggs might have been a little bit older. But Noel Whelan was playing in that Leeds team, and funnily enough Leeds won. As individuals they weren't as good as Man United but as a team they were a really good team.

That might lead you on to your next question."

Celtic have lost only one home European tie to British opposition in their history, to Brian Clough's Nottingham Forest back in the mid-80s, but that record is likely to be subjected to severe scrutiny midweek. Certainly no one will need to be more closely watched than the thirtysomethings who have been at the heart of the Old Trafford side's re-emergence as credible title challengers.

Scholes, who turned 32 this week, and Ryan Giggs, who will be 33 next week, have been playing like men possessed.

It is perhaps little surprise that Strachan picks out the identikit little ginger midfielder of the group for special praise. "I think he [Scholes] has been the best England midfielder for 30 years, " said Strachan. "I think you probably have to go back to Bobby Charlton for someone who can score goals, hit crossfield passes, do one-twos, beat people, and win headers in both boxes.

"What's more, he has managed all that without getting a headline, " Strachan added.

"He just does his job and goes home. So if you take that whole package I don't think there is anyone who has been so consistent. He has been doing that for 10 years.

"When the ball arrives at him, he could tell you where every player on the pitch is.

He needs to be more subtle because he has not got the physical presence of [Frank] Lampard, [Steven] Gerrard or most of the big guys that play in central midfield these days. He is like an old-fashioned inside forward, or a right half, then he goes in the box and he looks like he has been a striker all his life."

Then there is Giggs, the man who is now second only to the same Bobby Charlton for the number of appearances he has made for his illustrious old club. The Welshman now looks set to play on Tuesday night, after shrugging off a knock picked up on international duty against San Marino, and few people know more than John Hartson about his abilities.

Indeed, the former Celtic striker believes Giggs may yet go down as not only the best player he has ever played with but the finest Welsh player of all time.

"He's 32 now, and he is still going really strong, which is full credit to him, " Hartson said. "He could play anywhere . . . you could play him left back and he would still be the best player on the park.

"He has got to be one of the best ever, " Hartson added."I've been really fortunate, and played with guys like Mark Hughes with Wales, and people like Giggsy and obviously Henrik [Larsson].

But he is up there, he's got to be, with the likes of John Charles and Ivor Allchurch, and could even go down as the greatest. Ian Rush has got 29 goals and that is the record, but there is no one in Wales who will argue that Giggsy wouldn't be up there.

He has got 60 caps, but it is amazing to think how many he could have had. He never even played in a friendly for seven or eight years.

"He has a Champions League medal under his belt already and we came ever so close to qualifying for a major finals when we lost to Russia in a play-off [for Euro 2004].

Wales are out of this qualifying campaign, and I'm not sure whether he will get too many more opportunities.

That is a crying shame. He has more or less done everything else there is to do."

When you add Wayne Rooney, Louis Saha and Cristiano Ronaldo into the mix you would be forgiven for believing Celtic would be unwise to turn up, but then FC Copenhagen didn't approach things that way.

Neither should you try telling that to Lee Naylor. His record for Wolves against Manchester United ended with one win and one loss and he "would settle for that record again" and he believes even players who play their home games in front of 75,000 people will be knocked off their stride by the atmosphere within Celtic Park.

A Celtic win on Tuesday night, coupled with a draw between Benfica and Copenhagen could yet see both teams qualify. Gordon Strachan and Alex Ferguson shaking hands and smiling warmly together? Now that would be worth seeing.