Chelsea have announced that midfielder N'Golo Kante has undergone surgery on a hamstring injury.
The 31-year-old initially sustained an issue on the second weekend of the season, forcing him to be withdrawn during the latter stages of the 2-2 draw with Tottenham Hotspur.
Kante had been expected to return to the squad after the international break, a prognosis which was on track as the Frenchman made appearances on the training pitch.
However, despite seemingly making sufficient progress, Kante did not feature in any of Graham Potter's squads at the start of October.
Amid reports from France, Potter confirmed last week that Kante had suffered a setback in his efforts to put himself back in contention and would see a specialist over the weekend.
On Tuesday evening, it was revealed that all of the relevant parties had agreed that an operation was the best course of action.
A Chelsea statement read: "N'Golo Kante has undergone an operation on his hamstring injury.
"The midfielder visited a specialist with the club's medical department to explore the options for his rehabilitation approach and it was mutually agreed for N'Golo to have surgery to repair the damage.
"Following a successful operation, N'Golo is now expected to be sidelined for four months."
While Kante has been blighted by fitness issues since his transfer to Chelsea in 2016, the World Cup winner has rarely been sidelined in the long term.
However, being ruled out for four months will result Kante in missing as many as 25 matches from August 14 up until the start of February.
The latest development comes at a time when Kante is out of contract at the end of the season and Chelsea must now be giving serious consideration to allowing one of their star players to depart as a free agent.
Much may depend on whether Kante is able to come through the final three months of the campaign unscathed, as well as the offers that he will inevitably receive from foreign clubs at the turn of the year.
Kante is the second Chelsea player in the space of three days to be ruled out of the World Cup after it was revealed that Reece James would miss eight weeks of action with a knee problem. body check tags ::
