Barcelona head coach Luis Enrique has described Andres Iniesta's injury blow as "terrible news".
The midfielder suffered a thigh problem during the Spanish side's comeback 2-1 victory over Bayer Leverkusen in the Champions League last night.
A statement from the club confirmed the injury but did not give any indication as to when Iniesta will be fit to play again.
When asked about the injury by reporters, Enrique said: "These are thorns in our side we have to shake off."
Barcelona are already without their star player Lionel Messi, who is expected to be sidelined for six to eight weeks with a knee ligament injury.