Thiago Motta may be out until 2018 after Paris Saint-Germain announced the veteran requires minor knee surgery.
According to a statement released on the PSG website, the 35-year-old has complained of increased pain in his right knee since the 0-0 Ligue 1 draw at Montpellier in September.
The Brazilian-born Italy international has started 12 matches for Unai Emery's team in all competitions this term.
But, should he go under the knife imminently to address the issue, Motta may not return until after the mid-season break.
Leading Group B in the Champions League by three points, PSG host Celtic in Europe next week, followed by a trip to take on title-holders Monaco, who are four points behind them in second place in the league, four days later.
They are also away to Bayern Munich on December 5, with a Ligue 1 clash at home to Caen the team's final competitive game of 2017.
PSG do not then play again until visiting Nantes on January 13.
