GROUP E:IN THE end, it will be remembered as the night Old Trafford fell for the charms of Dimitar Berbatov and the forward whose place he has taken was left to wonder what it means for the future. Spare a thought for Carlos Tevez because there cannot be many things more galling for a professional footballer than to establish a reputation as one of his team's more accomplished players and then find his manager had headhunted someone else for exactly the same position.
How, you wonder, did Tevez feel, sitting among the substitutes, hunched up against the cold, as Berbatov scored the goals to instigate this victory and flashed those black gloves in the direction of the Stretford End? Tevez did at least come off the bench, an hour into the game, and the crowd was quick to remind him that he still has a place in their affections.
But this was Berbatov's night, incorporating the fourth and fifth goals of his seven appearances as a United player and another poke in the eye for all those knee-jerk commentators who rushed into judging him on the basis of a couple of ordinary performances directly after signing from Tottenham Hotspur.
When Ferguson signed Berbatov at the start of September his old ally Carlos Queiroz predicted that the United manager would somehow find a way of squeezing Berbatov, Tevez, Ronaldo and Wayne Rooney into the same team. It has since become apparent, however, that: a) Queiroz was guilty of overestimating Ferguson's streak of adventure; and b) the odd man out is going to be Tevez.
There have been nine games since Berbatov's arrival and the harsh reality for Tevez is that his name has been in Ferguson's starting line-up in only three of them. It will not console him, either, that one of those was in the League Cup, a competition Ferguson has been accused of regarding as "the ginger stepchild of trophies".
When it comes to the games that truly matter there is now an established order. Ferguson has made it clear Berbatov should now be thought of as his first-choice striker while Rooney's own form has accelerated so much since the arrival of the Bulgarian that when he sized up a scissor-kick 18 minutes into the game it was almost more surprising that the ball did not arrow its way into the net.
The paradox about Berbatov is there are still times when he seems on a different wavelength from his new team-mates. He is, however, capable of some of the most exquisite touches.
The little flick that took the ball past Artur Boruc for the opening goal was the most damaging for Celtic, but the one that really oozed quality arrived four minutes later when he nonchalantly jabbed out his right boot to bring down a goal-kick dropping from the sky.
It is in those moments that you can forgive him for occasionally looking like he does not quite understand why everyone else is running around so much.
Berbatov is clearly the type who will decorate matches rather than dominate them.
Rooney, on the other hand, can always be guaranteed to put in a lung-splitting stint, while Ronaldo's directness and penetrative running was another theme even in those periods when United struggled to find their usual cohesion.
These are strange times for Ronaldo. He spent so long over the summer pining for his "dream" move to Real Madrid and acting the part of Violet Elizabeth Bott - "I'll thcream and thcream 'till I'm thick" - this is a period when supporters are studying his body language for signs of discontent.
His response to scoring against West Bromwich Albion on Saturday was peculiar, to say the least. His name is no longer sung with the same appreciation and gusto and some of the tricks and feints that came off for him last season are temporarily out of order.
Nobody, however, could sensibly argue that his effort is no longer what it was. He alone made it a breathless night for Lee Naylor, a left-back best known in England for his time in a moderate Wolverhampton Wanderers side.
United did not reach their most exhilarating levels but they did not have to against opponents of this quality. Celtic's away record in the Champions League is now 18 defeats in 19 games while Gordon Strachan has lost all 10 of his matches here as a manager, four each with Coventry City and Southampton and two with Celtic.
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