Barcelona's injury woes deepened on Tuesday when tests showed that their Spain playmaker Xavi had a muscle problem in his left leg and might not be available for Saturday's La Liga game at home to Granada.
"Xavi is a doubt against Granada," the Spanish champions said on their website (www.fcbarcelona.com).
"The player will continue with a specific programme and his development will determine his availability for the next match," they added.
Barca are already missing World Player of the Year Lionel Messi, who was ruled out for up to eight weeks after tearing a muscle in this month's 4-1 La Liga win at Real Betis.
Defenders Gerard Pique and Jordi Alba worked apart from their team mates on Tuesday as they continued their recoveries, Barca said.
Midfielder Cesc Fabregas, who could replace Xavi in central midfield, again trained normally as he works his way back from a knee problem picked up in the Betis game.
Unbeaten Barca top La Liga by three points from Atletico Madrid after 13 matches, with Real Madrid a further three points adrift in third.
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