When does a mere game of football capture the imagination and become more than the proverbial 22 men chasing an inflated pigs bladder round a field?

Jose Mourinho, aka the (self appointed) “Special One”, aka Sir Alex Ferguson’s tormentor-in-chief, puts it thus: the “world will stop” tonight to watch a resurgent Real Madrid face Manchester United at Old Trafford.

And for many reasons.  It’s the first time Cristiano Ronaldo will grace the stadium he left three-and-a-half years ago for a then world record transfer fee of £80m.  It’s the 1,000th time Ryan Giggs will take to a playing field anywhere as a professional footballer. And the winner will progress to the quarter finals of the Champions League.

So lets lay out the stalls. United have effectively already won the Premier League, and should they beat Chelsea this weekend they will progress to the semi finals of the FA Cup.

Real have just completed a double of their own – back-to-back wins over Barcelona in both the Copa del Rey and La Liga.

How to split the difference?  The first of their Champions League ties in the Bernabeu ended with United coming away with a well-earned draw and the holy grail of knockout football – an away goal.

Real either have to win, or enter into a high-stakes gamble of a high scoring draw to continue their roll.  Yet it is indubitably the Spaniards who possess the fear factor. If Ronaldo manages to find his Higgs boson, as he invariably does against inferior opposition, United will find themselves dealing with the football equivalent of a Russian meteor strike.

And the talk of the town has not been an assessment of United’s own formidable strike power, but the high-stepping Portuguese.

“How do United contain Ronaldo?” – little else has been discussed of note since this glamour tie was first drawn.

Jose may well be right.  The world may indeed stop tonight.  Whether United’s defence will too is perhaps a more pertinent question.

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