Nathan Cleary needs multiple surgeries for a leg fracture suffered in the tackle that sent Phoenix Crossland off during Newcastle's preliminary final against Penrith.
The Panthers halfback is targeting a return at the start of next season, but will miss the Kangaroos' entire World Cup campaign.
Crossland was handed a four-game suspension, ruling him out of the NRL grand final and the opening part of the World Cup.
His tackle was accidental, and Crossland contacted Cleary to apologise. The Knights then won the preliminary final with 12 players for more than 40 minutes.
Crossland has now served his ban and is available for New Zealand. He is in the reserves for this weekend's semi-final against Tonga and could make the bench as dummy-half cover.
After Newcastle's grand final loss to the Roosters, coach Justin Holbrook told SEN Radio he would back a rule allowing players to defer suspensions for major games after accidental incidents.
"100 per cent. As I said, it's hard…for anyone to have a chance of a grand final. Phoenix is a local junior, played his whole life here. To finally get into a grand final," Holbrook said when asked about a possible change to the rules.
"It is foul play, it's a dangerous tackle we wants it out of the game. But it also still an accident how he got in that position. He hasn't flown out of the line and put a high tackle in. I definitely support it…I really felt for him."
Holbrook suggested a player could serve a longer suspension after postponing it for a grand final. He also said Crossland's absence hurt Newcastle's chances.
"We had Phoenix Crossland, who was a huge part of the year, he was obviously missing. And we were missing a couple of the front-rowers. So they were always going to play that power game as they always do," Holbrook said.