Yes, Barcelona might look like a side on the skids – no wins in eight, 10 points from nine, four games without a win, worst form in four years and any other stat that might make Manchester United fans feel a bit less nervous. But take a look at Lionel Messi in the Catalan derby on Saturday night and it’ll tell you that anything – anything – might happen. (There are some highlights on footytube, although they are somewhat distracting because of the bizarre commentary team. Who’s the Geordie who keeps interrupting the American and makes Jonathan Pierce sound laid back?) Anyway, Lionel Messi only took the field after half time but he showed how much United have to fear. Also, you won’t see many misses from Samuel Eto'o like the header the Cameroonian failed to connect with.

Can United contend with Messi – a  player light years ahead of anything Roma had on offer in what proved to be a surprisisngly poor display at Stadio Olympico? No-one knows, of course.

Ferguson may opt to deploy Rooney down the left flank, as he did in Rome, to help support Patrice Evra in defensive duties. That might conceivably leave Cristiano Ronaldo alone up front. It worked a treat against a Roma side for whom David Pizarro, the playmaker, was too busy kicking Ronaldo to create much and Ferguson was ultimately lamenting that – with the game won - he hadn’t brought Rooney back into a more offensive role with Ronaldo much earlier.

But defence is the dimension which Ferguson should be most concerned with. Evra demonstrated against Blackburn that he is vulnerable to a high ball across the box – Roque Santa Cruz might have capitalised twice on that during Saturday's game.

Wes Brown also had the kind of game at Ewood Park he’d like to forget and might have been booked for taking out Brett Emerton in the second half. And is it just me, or has Rio Ferdinand looked well beneath his best at times in the past month? Then there's the mutual dithering with Edwin Van der Sar which presented Emmanuel Adebayor with Arsenal’s opener at Old Trafford on April 13. There was also the patent error which opened the door for Blackburn. Morten Gamst Pedersen, a nemesis for United as he often seems to be, did him with a looping cross which squirted out for Santa Cruz.

Unduly negative talk? Pessimistic? Hopefully so. United deserve the Champions League trophy and there’s a feeling at Old Trafford that if they don’t take it again this year then they never will. But it all adds up to a night to remember.

A colleague penned a reminder recently of Jorge Valdano’s assessment of last year’s Chelsea/Liverpool semi-final. “Very intense, very collective, very tactical, very physical and very direct," said the former Real Madrid coach. "But a short pass? Noooo. A feint? Noooo. A change of pace? Noooo. A one-two? A nutmeg? A backheel? Don't be ridiculous. None of that. If football is going the way Chelsea and Liverpool are taking it, we had better be ready to wave goodbye to any expression of the cleverness and talent we have enjoyed for a century."

You can expect nothing of that sort come Wednesday.