Manchester City manager Pep Guardiola has confirmed that influential defender Aymeric Laporte faces up to six months out after undergoing knee surgery.
Laporte damaged cartilage and the lateral meniscus in his right knee after a clash with Brighton's Adam Webster in City's 4-0 win on August 31.
City reported that Laporte had undergone successful surgery in Barcelona, but did not specify how long they expected the Frenchman to be sidelined.
Guardiola confirmed the Frenchman will not return before next year and could even miss the start to the knockout stages of the Champions League in February, should the English champions advance to the last 16.
"Long (time). Five months, six months," said Guardiola when asked how long he expected to be without his defensive lynchpin.
"Next year (for) sure. January or February."
Laporte will be missed with centre-back one of the few positions where City are not blessed with great strength in depth.
The Premier League champions did not buy a replacement for departed former captain Vincent Kompany in the summer transfer window.
Midfielder Fernandinho is expected to deputise at the heart of the defence with John Stones and Nicolas Otamendi the only two senior centre-backs available to Guardiola.
City may be tempted to reinforce their defence when the transfer window re-opens in January.
However, speaking ahead of his City testimonial this week, Kompany said he trusted Guardiola to find the solution.
"By losing Laporte you lose a big player. You need big players in the bigger games but the key strength of this Manchester City team is relying more on the system than the individuals," said the Belgian.
"I don't see City weakening. Pep is way too aware of this danger to let it happen."