Barcelona, Oct 23: Scottish champions Celtic are unbeaten in their last five away games in Europe and are in stunning form in their domestic league but the Hoops face their biggest examination at Camp Nou against Barcelona in the UEFA Champions League group stage.
Celtic boss Neil Lennon admits pressure ahead of the clash against the Catalan giants but Tito Vilanova's side are vulnerable at back after conceding four goals in a nine-goal thriller against Deportivo La Coruna.
Barcelona miss key players at the back, defenders Carles Puyol, Gerard Pique and Daniel Alves are all sidelined for the Champions League clash.
Alex Song and Javier Mascherano are likely to partner in central defence while young right-back Martin Montoya will replace injured Alves.
Sergio Busquets will begin his two-match suspension for his red card against Benfica while Xavi Hernandez, who came off the bench against Deportivo, will start in his place.
Celtic have few injury concerns after James Forrest and Scott Brown returned to training despite not making the Scotland's squad and missing out the clubs 5-0 win over St Mirren at the Weekend.
Mickael Lustig, Emilio Izaguirre and Georgios Samaras also missed Saturday's clash but all three are expected to be selected for the trip to Barcelona.
*Barcelona are unbeaten in 17 UEFA Champions League games while Lionel Messi is the top-scorer in last four editions of the Champions League.
*Celtic managed just one away win in 27 away games in Europe. The 2-3 win over Spartak Moscow.
Barcelona (4-3-3): Valdes-Montoya, Song, Mascherano, Alba-Fabregas, Xavi, Iniesta-Alexis, Messi, Pedro
Celtic (4-3-3): Forster-Lustig, Wilson, Mulgrew, Izaguirre-Wanyama, Brown-Forrest, Ledley, Commons-Hooper