Benjamin Mendy's torn ACL and Sergio Aguero's fractured rib forces Pep Guardiola into some squad changes at Stamford Bridge.
Chelsea host Manchester City at Stamford Bridge in a top of the table clash on Saturday evening.
Both Premier League title rivals will be aiming to secure a vital victory but at the same time will be desperate to avoid defeat.
Here's all you need to know ahead of Saturday's gigantic clash.
Manchester City went into this fixture knowing they needed a win to apply pressure on arch rivals Manchester United in the 2011/12 title race. Chelsea went ahead on the hour mark as Gary Cahill's deflected shot found its way into the Citizens' net.
Roberto Mancini then turned to the previously exiled Carlos Tevez, who was making his first appearance for City since falling out with the Italian manager.
The introduction of the Argentine changed the game and the home side were level 18 minutes later thanks to a Sergio Aguero penalty.
Tevez then slipped a pass into Samir Nasir with five minutes remaining and the Frenchman kept his cool, slotting the ball into the back of the net to secure a crucial win for City and complete Tevez's redemption.
Chelsea defender David Luiz will serve the final game of his three-match ban, while deadline day signing Danny Drinkwater is yet to play a game for the Blues and is yet again ruled out through injury.
Manchester City captain Vincent Kompany is a doubt for the fixture with a slight injury, while the Citizens' first choice left-back Benjamin Mendy could have played his last game for the club this season following confirmation he injured his ACL against Crystal Palace.
Sergio Aguero fractured a rib in a car crash while in Argentina recently and the Manchester City talisman will be ruled out of Saturday's crucial fixture.
Predicted Chelsea XI: Courtois; Azpilicueta, Cahill, Rudiger; Moses, Kante, Bakayoko, Alonso; Hazard, Pedro; Morata
Predicted Manchester City XI: Ederson; Danilo, Stones, Otamendi; Fernandinho; Walker, De Bruyne, Silva; Sterling, Sane, Jesus
Following their sensational last minute win over Atletico Madrid on Wednesday evening, Chelsea will be going into this game with a great deal of confidence.
The Blues have the advantage of hosting the match and the Stamford Bridge crowd will be doing everything possible to be Chelsea's 12th man.
Manchester City have had a day longer to rest than the home side following their victory over Shakhtar Donetsk on Tuesday evening.
However, squad morale could be affected by the news of Benjamin Mendy being ruled out for the rest of season and Sergio Aguero's reported car crash.
Both sides will know a defeat would be a big blow in a title race that looks as though it will be very tight from what we've seen so far this campaign.
As a result of this, a cagey affair is likely to unfold with neither club taking too many risks in fear of losing to a title rival.
Prediction: Chelsea 1-1 Manchester City