Inter Milan central defender Walter Samuel could miss the rest of the season after suffering serious damage to his cruciate knee ligaments.
Tests on Sunday confirmed his injury and Inter issued a statement saying: "In the coming days reconstructive surgery will be planned."
Samuel, the latest in a string of Inter players to be injured, went down in severe pain after landing on a straightened leg in Saturday's 1-1 Serie A home draw with Brescia.
The defender was out for almost a year after suffering a similar injury in 2007.
Since coming back Samuel has formed a fearsome central defensive partnership with Lucio which was key to Inter winning the Champions League, Serie A and Italian Cup last term.
Ivan Cordoba looks set to deputise for Samuel in the short term with Marco Materazzi and Cristian Chivu the other options at center back, unless Inter decide to buy in January.