Gold Coast defender Harrison Wigg has torn his anterior cruciate ligament at training.
The 22-year-old went down during a training session on Thursday morning, with scans revealing the extent of the injury.
Gold Coast general manager of football operations Jon Haines said the injury was devastating news.
“It’s really unfortunate for Harrison, he had an injury interrupted season with the club last year, but had put together a really strong pre-season,” Haines said.
“We’ll make sure we provide as much support as we can for Harrison, and it’s been great today to see the way the whole football club has got around him to show their support.
“We were excited to see Harrison play some consistent football this year as we know what he can provide for us both on and off the field.
“We know he’ll approach his recovery with the professionalism he has shown this pre-season and we look forward to seeing him back up and running.”
Teammate Josh Schoenfeld will also miss the first couple of weeks of the season after undergoing ankle surgery.