Midfielder limped off during France's World Cup qualifying win over Bulgaria last Saturday
Conte on Kante: Chelsea star out for three weeks
Chelsea expect to be without midfielder N'Golo Kante for three weeks due to the hamstring injury he suffered on international duty.
Kante limped off in the first half of France's 1-0 World Cup qualifying win over Bulgaria last Saturday and boss Antonio Conte is resigned to being without him for the rest of October.
"Kante is going to do another scan next week to check if his situation is improving. From the previous scan, maybe he will be out for around 20 or 21 days," Conte said.
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Conte also looks set to be without Danny Drinkwater, who has a calf problem, for the next seven games starting with Saturday's Premier League trip to face Crystal Palace.
"In Kante's situation you have to have another scan to understand the situation very well," Conte said.
"He is a big loss for us because we know very well the importance of Kante to our team and we don't have another player with his characteristics.
"Danny is progressing well but is not ready yet. We must have patience with his calf problem. We may have to adapt some defenders into midfielders."
Alvaro Morata will also sit out the London derby at Selhurst Park but could return in time for the Champions League clash with Roma on Wednesday.
Striker Morata missed international duty with Spain due to a hamstring injury sustained against Manchester City on September 30, but initial fears of a long lay-off have receded.
"I hope to have Morata back very soon, I hope for the next game," Conte said.