Dani Alves looks set to miss Barcelona's next five games after picking up another muscle injury in what has been a stop-start season for the Brazil right-back.
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Alves limped off after just 13 minutes of his club's 4-0 win at Levante on Sunday, and his replacement for that game Martin Montoya looks set for another extended run in Barca coach Tito Vilanova's first XI.
Tests carried out back in Barcelona on Monday morning found that Alves had strained his right hamstring, with the news confirmed on the club's official website.
"Dani Alves will be sidelined for 15 to 20 days according to the Club's Medical Services this Monday," the statement said. "The right back underwent additional tests that confirm that the player has pulled the hamstring in his right leg.
"The Brazilian defender is recovering from the same injury he picked up last season, only this time the injury is in a different leg."
Alves missed most of October's action after suffering a thigh injury against Real Madrid in La Liga, but Vilanova will have been reassured by Montoya's impressive perfomances when deputising.
Utility man Adriano Correia is also available to cover after making his return from injury as a late substitute at Levante's Ciutat de Valencia stadium.
Alves joins fellow defenders Marc Bartra, Marc Muniesa and Eric Abidal, as well as attackers David Villa and Alexis Sanchez on Barca's injury list.
In more positive news for Blaugrana fans, young winger Isaac Cuenca returned to training with his team-mates on Monday morning after six months out with serious knee ligament damage.
The appearance of Cuenca, 21, was the main news from Barca's training session on at the Camp Nou, where the first team squad underwent a light recovery session. Villa was also present and looks close to a return from the light knock which saw him miss the Levante game and last week's 3-0 Champions League win at Spartak Moscow.
Barca face Alaves in their Copa del Rey last 32 second leg at the Camp Nou on Wednesday evening. Vilanova is likely to rotate his squad with last year's competitions winners 3-0 up from the first game.