Leicester City defender Robert Huth is expected to be out for six to eight weeks after ankle surgery.
The 32-year-old has not travelled to Hong Kong with the rest of the Foxes squad as he begins his rehabilitation.
"He's had an operation and thankfully it was successful," said Leicester boss Craig Shakespeare. "We thought it might be worse."
Shakespeare also confirmed there have been no bids for winger Riyad Mahrez, who said in May he wanted to leave.
The Algerian, 26, has been linked with Arsenal, with boss Arsene Wenger admitting his interest in the player.
"Riyad stated his position very clearly," Shakespeare said. "Mine is really simple: while he is here - and we haven't had any bids, it's all been speculation - he has to be committed to the club.
"In the two weeks he's been back, he's been totally committed and really trained well."
Leicester start their Premier League campaign with a game at Arsenal on Friday, 11 August before hosting Brighton and visiting Manchester United.
BBC Radio Leicester commentator Ian Stringer
Huth being out is a blow, but may actually help Shakespeare with his selection given new signing Harry Maguire is likely to go straight into the starting XI.
What the Foxes will lose is the German's experience in the dressing room, as well as his commanding displays on the pitch.
The club say the surgery has gone well, which gives him a chance of being back in the side in early October, given he will need time to get fit following his recovery.