Standard Sport revealed on Sunday morning that Courtois had sustained the injury in training and did not travel to Manchester with the rest of the squad, with Asmir Begovic set to step in to replace the Stamford Bridge No.1.
Despite that setback, Antonio Conte is able to name an otherwise first-choice XI to take on Jose Mourinho's Red Devils at Old Trafford, with Nemanja Matic preferred to Cesc Fabregas in central midfield.
Marcus Rashford is a surprise starter for United with Zlatan Ibrahimovic on the bench, as the striker suggested in the build-up to today's game that he was feeling the strain of the season.
Chelsea starting XI: Begovic; Azpilicueta, David Luiz, Cahill; Moses, Kante, Matic, Alonso; Pedro, Diego Costa, Hazard
Subs: Eduardo, Zouma, Terry, Loftus-Cheek, Fabregas, Willian, Batshuayi
Manchester United starting XI: De Gea, Valencia, Bailly, Rojo, Darmian, Fellaini, Herrera, Young, Pogba, Lingard, Rashford
Subs: Romero, Blind, Fosu-Mensah, Shaw, Carrick, Mkhitaryan, Ibrahimovic
Chelsea starting XI: Courtois, Azpilicueta, Luiz, Cahill, Moses, Kante, Matic, Alonso, Pedro, Costa, Hazard.