Juventus manager Max Allegri has confirmed that Joao Cancelo will require surgery on an issue with his medial meniscus, and will be sidelined until after the winter break.
Speaking before Juve's visit to Torino, the boss also gave an update on the condition of Juan Cuadrado, saying (via Juventus' official Twitter) that he will be assessed in the coming days over potential "small" surgery.
Cancelo has been Juve's first choice right back since joining from Valencia in the summer, but in addition to the Torino clash, will now miss home ties with Roma and Sampdoria, and the intersecting midweek trip to Atalanta with the knee injury.
A likely return date looks to be the Coppa Italia round of 16 visit to Bologna on 12 January after the break - but it's unclear exactly how long a recovery period will be required for the surgery.
It comes as a blow to Juventus, who have been on fire both domestically and in Europe so far this season, sitting eight points clear of Napoli, having dropped points just once in their 15 matches so far.
In the Champions League, Juventus advanced to the knockout stages as group winners with minimal fuss, and are one of the outright favourites for the competition.