What a difference a weekend made. Chelsea entered the last one as favourites to win the English Premier League (EPL). Yet after each side had played one game, that mantle passed to Manchester City.
What a difference the season's second weekend could make. Chelsea, who were top or joint top for 274 days last year, will find themselves five points behind their title rivals if they lose at the Etihad Stadium tomorrow.
It would not be an insurmountable gap, but it would be unlike them.
Jose Mourinho's Chelsea are natural front runners. He likes to impose his authority immediately and his three Premier League titles have all been built on the back of long unbeaten starts.
City are often fast finishers, clinching their crowns on the final day, but there could be a role reversal.
These two clubs, with City big spenders and Chelsea yet to strengthen the starting XI, tend to be opposites: City were last season's top scorers, Chelsea the possessors of the best defence.
Their differences have increased in the last week. Manuel Pellegrini's team were slick and skilful in their 3-0 win over West Bromwich Albion Tuesday. Whether in pre-season, the Community Shield or last Saturday's draw with Swansea, Chelsea have been mediocre on the field and increasingly argumentative off it.
Mourinho signed a new contract on the same day as Pellegrini, but whereas the Chilean seems content, the Portuguese appears fractious.
He has criticised officials and his own medical staff. He was unhappy that goalkeeper Thibaut Courtois was first dismissed against Swansea and then banned. But an appeal failed and this is the first meaningful test of his deputy Asmir Begovic, who excelled for Stoke but is in an environment now where every error could have greater consequences.
Pellegrini has to decide whether to use his most potent marksman against Chelsea's second-choice shot-stopper. Sergio Aguero missed pre-season and is being eased back to full fitness, but City looked potent enough without him at the Hawthorns.
But the sight of City could jolt Chelsea back to their best. Mourinho has an outstanding record against Pellegrini, who dislikes the Portuguese, and outwitted him at the Etihad Stadium 18 months ago.
That same blueprint - a 4-2-3-1 formation with a narrow defence, deep-lying holding midfielders and swift counter-attacks - is likely to be deployed again.
City will have the majority of possession but Chelsea will try to form an iron block in front of Begovic's goal, limiting the space afforded to David Silva and Yaya Toure.
The chances are that Cesc Fabregas, who can sometimes be a defensive liability, will instead be shifted forward to operate as a No. 10 so that Kurt Zouma, John Obi Mikel or Ramires can come in.
Mourinho is the strategist, Pellegrini the adventurer. The City manager has to show he can outmanoeuvre the top tacticians. His Chelsea counterpart, however, has to illustrate that trouble is not already brewing at Stamford Bridge.
MANCHESTER CITY V CHELSEA
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