John Terry is not fit to play so Gary Cahill will partner Branislav Ivanovic in central defence.
David Luiz plays alongside Frank Lampard in the centre of midfield with Ramires, who like David Luiz is playing against his former club, in a wide right position. It is the Brazilian’s 150th Chelsea game.
Oscar is on the left and Fernando Torres leads the attack. John Mikel Obi returns from injury to be on the substitutes’ bench.
For Benfica, Andre Almeida moves from left-back to replace suspended Maxi Pereira at right-back with Melgarjo coming in on the left. Former Chelsea man Nemanja Matic is in the centre of midfield. Pablo Aimar is only among the subs.
Chelsea are expected to line up in the following 4-2-3-1 formation:
1 Petr Cech
28 Cesar Azpilicueta
2 Branislav Ivanovic
24 Gary Cahill
3 Ashley Cole
4 David Luiz
8 Frank Lampard (c)
10 Juan Mata
9 Fernando Torres
Substitutes: 22 Ross Turnbull, 19 Paulo Ferreira, 57 Nathan Ake, 12 John Mikel Obi, 21 Marko Marin, 30 Yossi Benayoun, 13 Victor Moses.
Benfica are expected to line up in the following 4-3-3 formation:
Artur; Almeida, Luisão (c), Garay, Melgarejo; Peréz, Matić, Rodrigo; Gaitán, Cardozo, Salvio
Substitutues: Paulo Lopes, Jardel, Urreta, André Gomes, Aimar, Lima, John.
The referee is Björn Kuipers from the Netherlands.
Follow the game via our Live Matches from 7.15pm (UK time).