Guardiola and his players can secure the Premier League title against their rivals on Saturday, but even if United can prevent a City win, it will only delay the inevitable.
Manchester City v Manchester United: Mourinho can try to win the battle but the war is already lost
For decades, the scenario would have seemed ludicrous enough, let alone the possibility that it could appear a consolation prize.
Manchester City could clinch the Premier League title on the earliest ever date – 7 April – on Saturday. Uefa Champions League disappointment at Anfield should not disguise how auspicious this week could prove.
City have reduced Manchester United to the ranks of potential party-poopers, the team whose best-case scenario is to delay the title celebrations, whose aim is to ensure they avoid the ignominy of witnessing others secure silverware that once felt their private property.
The Premier League crown would come laced with symbolism if United were the inadvertent kingmakers. Pep Guardiola and Jose Mourinho have been competing claimants to the throne. The Portuguese felt summoned by United to counter the Catalan, their rivalry from Spain transported to Manchester because Mourinho was the lone manager to have denied Guardiola a league title.
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If he denies him another, it will be for a week; perhaps two at most. He may win the battle against his arch-enemy, but the war is lost. Because City will finish ahead of United for the fifth successive season or, to put it another way, every year since Alex Ferguson’s retirement.
Perhaps the shift in the balance of power in Manchester began in 2011, in the FA Cup semi-final when Yaya Toure scored the winner to facilitate City’s first piece of silverware in 35 years.
Certainly the notion the club Ferguson branded the “noisy neighbours” grew louder on the May day in 2012 when United finished their final game of the season at Sunderland, thinking they were champions, only for Sergio Aguero’s injury-time intervention at the Etihad Stadium to allow City to leapfrog United in the standings.
Ferguson briefly restored what was, for United, a sense of normality. He spent part of his retirement at Anfield on Wednesday, watching England’s last two representatives in the Champions League, City and Liverpool. They are now the bywords for attacking football, whereas his side once were.
And City against United has been a clash of clubs and a contest of ideas, just as Guardiola against Mourinho has long seemed purism against pragmatism. Idealism has tended to prevail.
The Portuguese has only suffered two home defeats to English opposition: both to City, both with the visitors out-passing his side and Guardiola out-thinking him.
Mourinho likes to argue his counterpart has outspent him. This can be seen as a footballing arms race, one host of superstar signings against another. But as Guardiola has pointed out, only two of his summer recruits, Ederson and Kyle Walker, have been regulars this season.
One of his targets, Alexis Sanchez, will be in United colours, so will the two costliest players on the pitch, in Paul Pogba and Romelu Lukaku.
The former club record signing Juan Mata may be sacrificed if, as he usually does against Guardiola, Mourinho stocks his side with defensive midfielders.
While most of the teams who have acquitted themselves best against City this year, from Wigan Athletic and Bristol City to Liverpool, have shown some attacking intent, United only need to draw to keep the title race mathematically alive. For the second successive season, Mourinho may play for a 0-0 draw at the Etihad Stadium.
The more instructive team selection will be City’s. Raheem Sterling should return to the starting line-up. Aguero may be fit enough to continue his quest for his 200th City goal against favourite opponents.
Yet there is the question if Guardiola rests players to spare them for the rematch with Liverpool. Vincent Kompany, the man married to a Mancunian, who has given a decade’s service but who has a famously fragile frame, is a case in point.
Few recognise the significance of the occasion better than the captain. “It would mean the world to our fans,” said Kompany last week. “I lived in Manchester long enough to understand how important it is to them.”
Guardiola stated weeks ago that the Premier League was his main priority, even if the suspicion is that he values the Champions League more. He spent some of last Saturday fielding questions if the Liverpool games were more important than the United fixture.
“I understand completely the enthusiasm to win the league at home against them,” he said. “Of course, I am not going to say ‘don’t be happy’ and ‘don’t dream to win the league’.”
And for years winning the league against United would have seemed a dream. Now it can become reality.