The Gold Coast Titans have lost captain Ryan James to a ruptured ACL in his right knee, with the forward to be sidelined for six months.
James, who suffered an ACL injury to his left knee in 2011, will undergo surgery on the injury after leaving the field 12 minutes into Sunday's win over the Newcastle Knights.
The injury appeared to occur after a collision with Knights hooker Danny Levi as he followed through a grubber kick near the Newcastle line.
"Unfortunately Ryan James has suffered an ACL tear," Titans head of performance Dan Ferris said on Tuesday.
"We've had scans to confirm that today and he'll have surgery this week and commence his rehab.
"It actually tore [before the collision]. He just caught in an awkward position when he extended the leg and it twisted inside and unfortunately the ACL didn't hold up.
"Knowing Ryan like I do, he'll do everything he possibly can to come back bigger and stronger.
Match Highlights: Titans v Knights
"I know he's hurting at the moment but we'll get the surgery done and commence the rehab straight away.
"He had one on the other leg in 2011 and showed extreme dedication in rehabbing that and hasn't had any injuries since.
"We feel for him at the moment but we know he'll get back to his best."
It's a major blow to a resurgent Titans team that has now won two straight against pre-season top-eight fancies Penrith and Newcastle.
The loss of James is offset somewhat by the return of Kiwi back-rower Kevin Proctor, who was a late withdrawal against the Knights after hurting his quad in warm-up.
In the only other change to Garth Brennan's side, Keegan Hipgrave has been recalled to the bench at the expense of Jack Stockwell.