A busy round of World Cup qualifiers last week caused France's Thierry Henry to be ruled out with a thigh strain, while Sweden's Zlatan Ibrahimovic missed Saturday's 0-0 draw in Valencia with a bruised knee.
"We spoke with the doctors and thought it best to be cautious (with Ibrahimovic)," Barca coach Pep Guardiola said after Saturday's La Liga clash.
"He was in a lot of pain. We'll have to see if we can get him back for Tuesday."
Ibrahimovic trained apart from the squad on Sunday, along with Seydou Keita, Eric Abidal and Pedro who all finished the bruising encounter in Valencia with knocks.
Lionel Messi completed the full 90 minutes in the Mestalla despite having played two emotionally draining qualifiers with Argentina last week and looked well below par.
"It is normal that sometimes you have off days," midfielder Keita said of Messi on Sunday. "The team weren't at their best either (against Valencia), but he remains one of our best players."
NOTHING TO LOSE
The Spanish league leaders have Bojan Krkic back after injury and Guardiola could draft him in to the attack if Ibrahimovic is not fit in time.
Barca also top their Champions League group with four points from two games, and host a Rubin Kazan side who will have been lifted after claiming their first point in Europe's elite club competition last time out.
The Russians held Italian giants Inter Milan to a 1-1 draw in Kazan last month and coach Kurban Berdyev was confident this result would help his side.
"We are playing Barcelona, the best team in the world, so we have nothing to lose and a lot to gain from the match," he was was quoted as telling local media.
Berdyev rested a number of key players for their 2-1 league win over struggling FC Khimki on Saturday, but suffered a scare when Russia striker Alexander Bukharov left the pitch after just three minutes with a leg injury.
"Thank God his leg is not broken and I hope he'll be ready in time for Barcelona," Berdyev said.
South African midfielder Macbeth Sibaya is suspended.
Probable teams:
Barcelona: Victor Valdes; Daniel Alves, Gerard Pique, Carles Puyol, Eric Abidal; Xavi, Seydou Keita, Yaya Toure; Pedro, Zlatan Ibrahimovic, Andres Iniesta.
Rubin Kazan: Sergei Ryzhikov; Cesar Navas, Roman Sharonov, Cristian Ansaldi, Lasha Salukvadze; Alexander Ryazantsev, Sergei Semak, Christian Noboa, Gokdeniz Karadeniz; Alejandro Dominguez, Alexander Bukharov.
