Paulo Dybala remains a doubt to face Tottenham Hotspur in the Champions League next month after further tests on the Juventus forward's damaged thigh confirmed initial fears.
Argentina international Dybala, 24, sprained a thigh in Juve's 1-0 win over Cagliari in their final fixture before Serie A's two-week winter break on Jan. 6 and was initially expected to miss up to six weeks.
The Bianconeri resumed training on Tuesday after a nine-day break, but Dybala -- together with Claudio Marchisio, who has an adductor injury -- was instead in the treatment room, with neither expected back until the first week of February at the earliest.
"Dybala and Marchisio are both expected to be out for between 30-40 days after the assessments made in the first week of January," according to the club's website.
Juve host Tottenham in the first leg of their round-of-16 Champions League clash on Feb. 13, which will be 37 days after Dybala picked up his injury.
He will miss the Bianconeri's Serie A clashes with Genoa, Chievo Verona, Sassuolo and, with all probability, Fiorentina in the run-up to the resumption of European football in 2018.
Dybala has scored 14 goals in 19 Serie A fixtures this season, although he has failed to find the back of the net in six Champions League appearances.
Meanwhile, Gianluigi Buffon and Juan Cuadrado could both be in contention to face Genoa on Monday, with "both recovering well" and set to "follow a personalised training regime this week," according to the club.
Buffon needs to appear in the game to have any hopes of equalling Paolo Maldini's record of 647 career Serie A appearances this season.