David Luiz, Ryan Bertrand, Ramires and John Obi Mikel are on yellow cards and may not be risked as the Blues take a 2-1 first-leg lead into the contest with the Swiss champions.
Ramires suffered a dead leg in last Sunday's defeat of Swansea and could be rested anyway, with Sunday's match at Manchester United in mind, while definite absentees are the ineligible Demba Ba and Oriol Romeu (knee).
- Sports & Recreation
- John Obi Mikel
- Ryan Bertrand