Making his first hit-up of the match just two minutes into the game, Lussick hit the ground writhing in pain and clutching at his ankle.
Lussick was then assisted from the field by two trainers and it was clear the injury was serious.
“Not good,” Sea Eagles head coach Trent Barrett said post-match.
“We’re still waiting to see how bad it is but it doesn’t look particularly good at this stage, which is a shame for Darcy.
“He’s had a good pre-season and it was the first tackle of the game. We’ll cross our fingers and hope he’s alright.
“Trials are a necessary evil I suppose. I’m just disappointed for Darcy.”