The Blues kept themselves busy in the winter transfer window, as they sold club hero Juan Mata to Manchester United and signed Mohamed Salah from Basel as replacement. However, the Egyptian is unlikely to make his debut against the Hammers.
Chelsea are heading into this match on the back of a 1-0 win over Stoke City in the FA Cup, and Mourinho is expected to make few changes from the team that played on Sunday.
In the defence, John Terry and Cesar Azpilicueta are expected to return, while David Luiz may retain his place.
Nemanja Matic was solid against Stoke City and the Serbian could start tomorrow alongside Ramires, while Frank Lampard could be rested.
Andre Schurrle started in the last match in place of Willian, but the German is likely to make way for the Brazilian. Fernando Torres is out injured so Samuel Eto’o will retain his place as a lone striker.
Prediction: 2-0; Chelsea have won 11 of their last 12 home matches in the Premier League and should win this tie comfortably as well.