England international and former Arsenal attacker both miss out on the starting lineup while David Luiz is absent for the Blues through suspension, replaced by Jose BosingwaChelsea and Manchester City are both without big names for their Premier League encounter, with Frank Lampard and Samir Nasri missing out on the starting lineups.
Questions over Lampard's future are bound to dominate now, having missed out on the Blues' crunch encounter with Valencia last week, and now he sits out perhaps one of the most decisive encounters of the season.
David Luiz is also absent for the hosts through suspension, the Brazilian being replaced by Jose Bosingwa at right-back, with Branislav Ivanovic moving to centre-back.
Former Arsenal star Nasri has been a peripheral figure for City so far this season, with Mancini admitting after the League Cup tie at the Emirates that the Frenchman "can improve".
Chelsea (4-3-3): Cech; Bosingwa, Ivanovic, Terry, Cole; Ramires, Meireles, Romeu; Sturridge, Drogba, Mata.
Subs: Turnbull, Lampard, Torres, Mikel, Malouda, Ferreira, Kalou.
Manchester City (4-2-3-1): Hart; Zabaleta, Kompany, Lescott, Clichy; Yaya Toure, Barry; Milner, Silva, Balotelli; Aguero.
Subs: Pantilimon, Dzeko, Johnson, Savic, Nasri, Toure, De Jong