Barcelona forward David Villa fractured his leg during the Club World Cup semi-final against Al Sadd of Qatar on Thursday, the Spanish champions said.
"Bad news for David Villa and Barca, the striker's left tibia is fractured," Barcelona said on their Twitter feed.
"The player has been taken to the Yokohama Rosa hospital for further tests."
Barca said it was the first injury Villa had sustained since joining the club from Valencia last year.
The news is a blow for Barca coach Pep Guardiola as they pursue titles in the Club World Cup, La Liga, the Champions League and the King's Cup this season.
Spain coach Vicente del Bosque will also be concerned as Villa is the country's leading striker looking ahead to the defence of their title at Euro 2012 in Poland and Ukraine.
The 30-year-old is Spain's all-time top scorer with 50 goals in 81 appearances and played a central role in them winning the World Cup in South Africa last year.
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