Manchester City were on the verge of immortality last season, on course to win an unprecedented Quadruple, until they ran into Thomas Tuchel's new, improved Chelsea side. Three games against Chelsea ultimately defined City's season.
That trilogy of defeats started in the FA Cup semi-finals after Pep Guardiola had made eight changes to his starting line-up, and was followed by a loss in the Premier League after Guardiola made a further nine changes.
Those two matches sparked a huge transformation in the Chelsea players, who then had the confidence to beat a full-strength City in May's Champions League final.
Familiar rivals Thomas Tuchel (L) and Pep Guardiola meet in the Premier League on Saturday
Tuchel is on a formidable run with Champions League winners and early table toppers Chelsea
But Saturday is an opportunity for City to redress the balance of power and shift it back in their favour by returning to the form of last season, when they won 21 matches in succession between November and March. Even at this early stage, I consider this a must-win game for City.
Top-of-the-table Chelsea are unbeaten this season (W4, D1), having faced Arsenal, Liverpool and Tottenham away.
Tuchel is a coach totally in touch with his team's performances. At Tottenham last week, there was an uncharacteristic lack of desire and control in the first half, so he cracked the whip and replaced Mason Mount with N'Golo Kante at half-time.
In the second half, it was all Chelsea, thanks to a change in mood which was created by their manager. After today, Chelsea have a run of inviting games. Beat City and they'll be feeling unstoppable with their upcoming fixtures.
Let's not forget what is at stake. Chelsea took away the Champions League from City just 119 days ago and now they're coming to take their Premier League title, too.
The German had the better of Guardiola when the sides clashed in the Champions League final
Heading into the Champions League final last May, one or both of Fernandinho
