Manchester City winger Leroy Sane faces up to seven months out with a knee injury, manager Pep Guardiola said ahead of Saturday's Premier League opener against West Ham United.

The 23-year-old Germany international damaged the anterior cruciate ligament in his right knee in City's Community Shield victory over Liverpool on Sunday, and will undergo surgery next week.

"It is incredibly bad news. I don't know how long he'll be out. Normally this kind of injury is six or seven months - hopefully February or March," Guardiola told reporters.

"In three seasons we've had three (knee ligament injuries). He's young and he'll recover well hopefully in terms of the surgery next week. All the people will help him, he will feel alone and we help him to feel as comfortable as possible."

Sane, whose contract expires in 2021, had been linked with a move to German giants Bayern Munich during the close season.

He has been offered an extension but has yet to sign, having struggled to seal a regular starting spot last season.

However, Guardiola was keen to stress that at no point had he entertained thoughts of selling the winger who was named PFA Young Player of the Year in 2017-18.

"I didn't think about him leaving. Always I said he's our player, and he didn't tell me he wanted to leave. Always I thought he was ours," he added.

Guardiola said his Spanish compatriot David Silva would take over as club captain following Vincent Kompany's departure at the end of last season.

"David has almost one decade here with the club, in the Premier League. He's incredible, he's been respectful to his teammates... He'll be a good captain," Guardiola said.

New right back Joao Cancelo is unlikely to feature in their league opener having arrived from Juventus on Wednesday.