It's arguably the most important game of the season so far tonight for Liverpool as they take on Barcelona at the Nou Camp in the Champions League.

The current holders Barca see a return from injury for Lionel Messi, whilst the competition's previous holders Liverpool give a debut to full-back Alvaro Arbeloa. Steven Gerrard looks set to start wide on the right and Javier Mascherano is on the bench.

Liverpool: Reina, Finnan, Arbeloa, Agger, Carragher, Gerrard, Riise, Alonso, Sissoko, Kuyt, Bellamy
Subs: Dudek, Hyypia, Pennant, Crouch, Gonzalez, Mascherano, Zenden

Barcelona: Valdes, Belletti, Marquez, Puyol, Zambrotta, Xavi, Motta, Deco, Messi, Saviola, Ronaldinho
Subs: Jorquera, Gudjohnsen, Giuly, Van Bronckhorst, Thuram, Oleguer, Iniesta

Referee: Kyros Vassaras (Greece)

Kick-off: 7.45pm GMT