Barcelona are sweating on the fitness of four key players before their Champions League game against Rubin Kazan on Tuesday.

Striker Zlatan Ibrahimovic started the Primera Liga game against Valencia at the weekend on the bench after failing to shake off an injury sustained during the international break.

Defensive midfielder Keita, winger Pedro and left-back Abidal are also injury doubts for the Rubin game after picking up knocks during Barcelona's 0-0 draw at Valencia.

According to the official Barca website, the players did not join the main squad for light training on Sunday but instead stayed in the dressing room area for therapy.

Ibrahimovic also missed the training session, working in the gym instead.