If Barcelona versus Real Madrid turned the stomach and Manchester United against Schalke followed a predictable script, then on Sunday Old Trafford will host a spectacle the like of which hasn't been seen in the Barclays Premier League for some time.
United versus Chelsea is as close to a title play-off game as we are likely to see. Not since Arsenal stunned Liverpool at Anfield in 1989 have two teams come together so late in the season with so much to be won and lost.
Round one: Chelsea beat Man United in the league in March to restart their title bid
'It's simple,' said United's Ryan Giggs this week. 'Both teams have to try and win.'
By his own admission, United manager Sir Alex Ferguson has been thinking about this game from the moment his side lost at Arsenal last Sunday. It occupied his thoughts before, during and after his team's dismantling of Schalke - and that says just as much for the task facing his men this weekend as it does for the manner in which their Champions League semi-final second leg had been rendered so humdrum by a 2-0 win in Germany a week earlier.
Nobody seeks to detract from United's achievement in reaching a third European final in four years. Win or lose to Barcelona on May 28, it has been a remarkable effort. Nevertheless, there has really been only one game that mattered this week.
Giggs, a certain starter on Sunday and against Barcelona at Wembley, said: 'Both teams realise this is the game that will decide it.
Round two: Man United beat Chelsea on their in the Champions League quarter-finals
'It's going to be difficult because Chelsea are a top team. But our form is good and we always fancy ourselves at Old Trafford.'
United's form is a moot point. Fine performances against Schalke and Everton have been interrupted by curious efforts against Arsenal (0-1), Newcastle (0-0) and Manchester City (0-1).
So United's form remains patchy, as does Chelsea's. Anyone who saw them labour at home to Tottenham will testify to that. Perhaps we shouldn't expect anything else. After all, Chelsea sprinted into an early eight-point lead over United this season, only to trail them by 15 points when the teams met at Stamford Bridge on March 1.
Chelsea midfielder Michael Essien said: 'It has been a sweet and sour season. To use a sandwich analogy: sweet bread at the top, sour filling and more sweet bread at the bottom. We started the season extremely well, had a sour middle and are ending strongly.
Phony war: Barcelona versus Real Madrid flattered to deceive
'We have hit a good run of form lately and have managed to haul ourselves back into the title race. We have to beat Manchester United and I can assure you we are up for it. The team are playing well and I have no doubt we will give it everything we have.'
United remain irritated by the nature of their loss at Arsenal and even more so by recent events against Chelsea. Last season an offside Didier Drogba goal ensured the Blues won decisively at Old Trafford while in March the London club won a game so controversial that Ferguson's analysis of it left him with a five-game touchline ban.
In retrospect, it can be seen that the day kick-started Chelsea's renaissance. Ferguson has been reminding his players of that behind closed doors this week.
'Both teams have to win': Ryan Giggs talked up Sunday's game
Carlo Ancelotti's side are playing to save their season and, indeed, their manager. The Italian's mid-season woes seemed to have cost him the love of Chelsea owner Roman Abramovich.
He has appeared to be wearing concrete shoes for quite some time. But surely not even London's most capricious Russian could jettison a coach who has just won him the league.
Chelsea are some way from doing that, of course. A win at Old Trafford would still leave them needing victory at home to Newcastle and away at Everton to clinch the title. The first game would appear a formality, the second would not.
Food for thought: Michael Essien compared Chelsea's season to a sandwich
United have games at Blackburn and at home to Blackpool to follow. It is hard, therefore, to see them slipping up. It remains possible that Chelsea could win at Old Trafford and still not win the league.
In a season undermined by the sheer mediocrity of the leading teams, that would in many ways be a completely appropriate finish.
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