Thomas Tuchel’s side are 10 points adrift of City having both played 21 matches.
If that point gap remains the same – or increases – this weekend, you have to feel it’s game over in terms of Chelsea title hopes.
But if it reduces to seven points with an away win, then it’s game on.
Of course, it’s not the first time these two teams have strived to win the league.
Ever since they were taken over by mega-rich owners, the ambition of both clubs is to win the Premier League every season.
That was certainly the case during the 2013/14 campaign. On that occasion, City came out on top, with Chelsea just four points adrift in third.
Quiz: Can you name the footballer based on their Wikipedia page?
But it was Chelsea’s victory over City at the Etihad in February that really breathed life in the title race.
It was City’s first loss of the season with Branislav Ivanovic scoring the only goal of the game.
Despite the rivalry, we wanted to remember a rather lovely moment at half time during that game – captured by Man City’s ‘Tunnel Cam.’
It occurred between City’s Yaya Toure and Chelsea’s Samuel Eto’o as Chelsea held a 1-0 lead after 45 minutes.
The two players appeared to clash as Eto’o wagged his finger in Toure’s face and squared up to him.
Referee Mike Dean was a few yards behind the pair and looked ready to pounce as he believed the two was about to fight.
But it soon became clear that they were just joking around as they swapped shirts.
And many fans in the comments section on YouTube translated what was said in French.
Eto’o joked that he would “slap” Toure because he was tired out after the first half.
“I’ll slap you though,” Eto’o said. “You exhausted me bro, really, I’m so proud of you I swear.”
Take a look (it occurs at 7:35 in the video).
VIDEO: Mike Dean thought Toure and Eto’o were about to fight
Eto’o lasted 83 minutes during the match and helped Jose Mourinho’s men pull off a fantastic victory.
Can they produce a similar performance – and result – and the Etihad eight years on?