Nerlens Noel has elected to undergo surgery on his ailing left, the team announced Friday and he is already doubtful to begin the season.
Noel reported soreness in his left knee while rehabbing his groin and was diagnosed with inflamed plica.
The surgery is considered minor and will occur within the coming days. He is without a timetable for return.
With Jahlil Okafor (knee) on a minutes cap to begin the season, Richaun Holmes could see additional minutes for the Sixers alongside Joel Embiid (foot), who is expected to weaned into his first full season.
Noel and the Sixers have until October 31 to work out a deal that will keep him from becoming a restricted free agent after this season.
Noel averaged 11.1 points and 8.1 rebounds per game last season.
The Sixers also announced backup guard Jerryd Bayless will be re-evaluated in two weeks after electing a non-surgical option to address a sore left wrist.
Philadelphia look to improve on their 10-72 record from 2015-16 when the team open up the new season Wednesday against the Oklahoma City Thunder.