The 22-year-old Benfica loanee pulled up in the second half of Celtic’s 1-0 win over Hearts on Thursday night and the injury is concerning enough to require a scan.
There are fears within Celtic Park that Jota may miss much of the December fixture list, which included the Premier Sports Cup final against Hibs on December 19. Celtic play eight matches this month before facing Rangers on January 2.
Jota is certain to miss the cinch Premiership match against Dundee United on Sunday, along with defenders Anthony Ralston and Stephen Welsh, who also limped off against Hearts.
Ralston has an ankle issue, while Welsh is also struggling with a hamstring complaint.
Celtic manager Ange Postecoglou is already without striker Giorgios Giakoumakis due to a knee problem, while centre-half Christopher Jullien continues to recover from a long-term injury.