Juventus midfielder Mohamed Sissoko has been ruled out for the rest of the season after undergoing knee surgery.
Sissoko has been troubled by a cartilage problem in his left knee for some time and had an operation in Bordeaux to fix the damage.
The former Liverpool player will now be sidelined for three months, meaning he will play no further part in Juve's bid to qualify for the UEFA Champions League.
The 26-year-old's absence is a further blow for Juve coach Luigi Del Neri, who will also be without midfielders Hasan Salihamidzic and Alberto Aquilani for Saturday's match against AC Milan.
Salihamidzic sustained a thigh problem in Tuesday's training session while Aquilani has yet to recover from a muscle injury.
Defender Fabio Grosso is also out for 10 days with a strain in his right thigh and striker Simone Pepe is suspended this weekend.
Juve have lost four of their last six league games and head into this weekend's showdown in seventh position in Serie A, 17 points behind league leaders Milan.