Newcastle has knocked Canberra out of the NRL finals with a nail-biting 30-28 extra-time win after Raiders star Jack Wighton avoided a send-off for an alleged bite on Tyson Gamble.

Captain Kalyn Ponga kicked an 89th-minute penalty which ensured the Knights will head to Auckland to face the Warriors next Saturday after securing a helter skelter victory in their first home final since 2006.

They will cross the ditch severely battered and bruised with concerns over the fitness of first-choice halves pairing Jackson Hastings and Gamble, both of whom failed to finish the elimination final.

But the biggest talking point from Sunday’s meeting in front of 29,548 at McDonald Jones Stadium will be the decision which allowed Wighton to stay on the field.

Gamble made a tackle on Wighton in the 47th minute, climbing to his feet and alleging to referee Ashley Klein that he had been bitten on the arm.

Tweet from @NRL

He showed the NRL official marks on his forearm, but Klein chose to only place Wighton on report, with insufficient evidence available to him.

The match was Wighton’s final outing for the Raiders before he joins South Sydney next year.

After Canberra rookie Hohepa Puru was taken for a head injury assessment and Greg Marzhew crashed in for the Knights after three minutes, it looked likely to be all one-way traffic in favour of the home side.

But a depleted Canberra had other ideas.

They motored up the middle of the field with ease and were able to take advantage of Newcastle continuously shooting themselves in the foot.

Wighton jolted the ball loose from Dane Gagai and James Schiller was able to run in to put the Green Machine level in the 18th minute.

Soon afterwards a short goal-line drop-out found its way into the hands of Raiders rookie Trey Mooney, who carried three Newcastle defenders over the line for his first NRL try.

Knights legend Andrew Johns described his former club as “shell shocked” in commentary for the Nine Network – but there was more to come.

Gamble hoofed a ball out on the full with less than 60 seconds left, with Wighton sending Schiller down the touchline to put the Raiders up 16-6 at the break.

Hastings failed to return in the second half due to an ankle injury but the biggest flashpoint came when Wighton took a carry out of his own end and was tackled by Gamble, leading to the latter’s appeal to Klein.

Newcastle fans were incensed that Klein only placed Wighton on report and the decision apepared to spark the home side.

The Knights clicked into gear, with tries to Kalyn Ponga, Gagai and two from Dominic Young helping them add 18 points in 16 minutes.

Canberra looked dead and buried but when Matt Frawley charged in to make it a six-point game with 15 minutes to go, they began to believe.

Former Newcastle junior Tom Starling pulled them to within two with three minutes left as a Jamal Fogarty conversion squared the game up and sent it to extra time.

Fogarty had two field goal attempts charged down but when Hudson Young was penalised for offside in the 89th minute, Ponga took a straightforward shot at goal to seal victory and book the Knights’ ticket to Auckland.

-AAP