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Ferreira: Ligament injury

Although Ferreira has only been on the fringes of the first team this season, having been displaced by summer arrival Jose Bosingwa, the news will come as a blow to Blues boss Guus Hiddink.

The Portuguese defender is the third Chelsea player to suffer a serious knee problem this season, withJoe Cole and Michael Essien also affected by ACL injuries.

Ghana international Essien is back in training with the reserves and has been included in Hiddink's squad for Saturday's FA Cup quarter-final against Coventry, while Cole is out for the rest of the season.

Ferreira, who joined Chelsea from Porto in 2004, has started just one Premier League game and appeared as a substitute in a further six matches.

But the 30-year-old is a hugely experienced defender at both international and at club level; winning two Premier League titles under Jose Mourinho at Chelsea and the Champions League in his final year at Porto, also under Mourinho.

Centre-back Ricardo Carvalho has shaken off a hamstring problem to boost Hiddink's defensive options for Saturday's FA Cup clash.

Chelsea's top scorer Nicolas Anelka is ruled out with a bruised toe and Portuguese playmaker Deco is missing with a muscle injury.