Scans today will confirm Zillman's fate, but Raiders' medical staff were already resigned to losing him for the season last night.

It is a horror blow for the 21-year-old, who has already had one knee reconstruction after suffering the same injury in round 21 last year.

Raiders prop Scott Logan also faces an extended period on the sidelines after fracturing his cheek, adding to a worrying list of injuries following just two rounds of the season.

Logan and Zillman join Queensland State of Origin back rower Neville Costigan and winger Brett Kelly on the long-term injury list.

Zillman is a particularly big loss for the Raiders.

After being knocked out in the opening half of last week's loss to Newcastle, Zillman showed his attacking brilliance last night when he dashed 80m to score an untouched solo try.

Just 35 minutes later he was limping off the field after twisting his knee on a kick return.

Raiders prop Josh Miller said his teammates would rally around their fallen teammate.

"I know what it's like myself having been through a knee reconstruction and for him to have to face it again so soon is terrible," Miller said.

"We're just going to miss him so much throughout the year because you saw how much he added to our attack tonight.

"It's going to be a big loss for the team and it's just so disappointing for Zilly.

"He's such a rising young star and such a talent and it's a pity we've got to wait another year to see it."