The Canberra Raiders fear a mistimed knee to Jarrod Croker's head could prematurely end his NRL finals campaign after he left Canberra Stadium bloodied and dazed yesterday.
The point-scoring ace will have scans to do to determine whether his season has come to a screeching halt or whether he can join his teammates in week two of the finals.
There were initial concerns Croker had broken his jaw, but the extent of the damage will not be known until this afternoon.
The Raiders trounced the Cronulla Sharks 34-16 yesterday to book a blockbuster clash with the South Sydney Rabbitohs at ANZ Stadium on Saturday night and keep their premiership dream alive.
But it was Croker's early exit with 13 minutes remaining which could cause coach David Furner a significant headache this week.
Croker was on the attack when he was tackled metres from the Sharks line in the second half.
He was on the ground when he copped an accidental knee from Sharks replacement Jayson Bukuya.
While it didn't appear intentional, players are not allowed to go into a tackle leading with their knees.
Bukuya was not put on report, but he could be cited and required to front the judiciary.
Croker couldn't get to his feet and had blood in his mouth as he left the field.
''I've got a sick kid in there. Crokes is no good,'' Furner said.
''The doctors are looking at him and he's not too well. I think it was a clash of the knee there.
''I know you can't do it, I know you can't lead with the knees. There's no doubt he's a sick boy.''
Croker is the NRL's leading point scorer this season and his goal-kicking ability is crucial to Canberra's hopes of continuing its winning streak to seven games.
When he left the field, Josh Dugan and Blake Ferguson both tried to fill his goal-kicking shoes, but failed to land a goal from four attempts.
Reece Robinson is also a capable kicker and if Croker is ruled out, Furner will decide which of the trio gets the responsibility for the clash with the Rabbitohs.
The Raiders are confident of continuing their end-of-season momentum, but captain David Shillington admitted Croker's potential absence would leave a massive hole in the line-up.
''Whether it was intentional or not, I don't know. But he [Bukuya] did lead with his knees at the end of the day and that's against the rules,'' Shillington said.
''That's up for the judiciary, but hopefully Crokes is right next week because he's a huge part of our team with his goal kicking and try-scoring ability.
''Fingers crossed he's right because he's an important part of the team.''