Wighton collided with Aidan Guerra and Jacob Saifiti mid-tackle, before his head slammed to the ground.

He was subsequently ruled out of the match with a failed assessment, leaving the Raiders a nervous wait ahead of Saturday's clash with the Wests Tigers.

"He's alright, I think it was only a couple of minutes before the end of the game that he could return if he had too," Raiders coach Ricky Stuart said.

A rollercoaster first-half showed just how vital Clive Churchill Medallist Wighton is to keeping the Green Machine's cogs turning.

His first handful of involvements compiled the Raiders' highlights reel, starting with a flying intercept that saw him breaking through the Novocastrians' line.

It took four Knights and an ankle tap to take him down.

Wighton scored the Raiders' sole try of the opening half, pouncing on a looping Jarrod Croker kick to narrow the margin down to four.

He nearly set up a second in the 10th minute with a flick to Charnze Nicoll-Klokstad on the left edge. Except the pass went forward. And through his hands.

Wighton went on to concede a penalty try in the dying minute of the first half, taking down Enari Tuala early to prevent him from finding the ball.

Elliot Whitehead burst onto Campbelltown Stadium clapping his hands in time with Canberra Raiders fans watching from afar.

The sound of the first virtual Viking Clap echoed through the empty stands, marking the Green Machine's new territory ... just 235 kilometres up the road.

Videos of 33 cheering households were compiled with footage of Viking Clap ambassador Terry Campese and Sia Soliola beating the drum.

But the taste of Canberra wasn't enough to continue their winning start to the season, with the Raiders suffering a 34-18 defeat.

The empty stands were sprinkled with green and the faces of Canberra and NRL fans.

Former Raiders chairman John McIntyre had 19 cardboard cut-outs of his family, while a group of players could also be spotted in the stands.

Joe Tapine could be in strife for throwing two jabs at a smiling David Klemmer moments after the Knights added to their tally with a late try.

Replays showed Klemmer charging down star Englishman George Williams to cause his pass to go astray in the final play.

The halfback's wayward pass to Siliva Havili was scooped up by Bradman Best, who went on to put the cherry on top of Newcastle's victory.

The referees took no further action after the scuffle was dispersed, but it could be revisited by the match review committee on Monday.

The Raiders' ($5) first loss of the 2020 season sees them fall behind the Sydney Roosters ($4.50) as premiership favourites, according to Sportsbet.