With Canberra trailing 18-14 and both teams out on their feet, second-rower Young gubber-kicked ahead in the 79th minute and won the race to the ball to score close to the posts.

Canberra halfback Jamal Fogarty converted to clinch a memorable victory for the home team, their fifth in the past six games.

A Greta-Branxton Colts junior, Young helped the Knights win the Harold Matthews premiership in 2014, playing alongside the likes of future Newcastle first-graders Brodie Jones and Brayden Musgrove.

But his promising career was almost permanently derailed as a 16-year-old when he tested positive to a banned substance that emanated from a supplement he bought in a supermarket.

He spent 18 months on the sidelines before the Raiders threw him a lifeline, offering him a spot in their under-20s.

He debuted in the NRL in 2019 - coincidentally against Newcastle - and has since become a mainstay in Canberra's pack, appearing in 62 top-grade games.

His performance on Sunday was arguably the best of his career. As well as his game-breaking try, the 24-year-old made 139 attacking metres and 33 tackles in a sensational all-round performance.

Another former Knights player was also a dominant force in the Green Machine's last-gasp victory.

New Zealand Test prop Joseph Tapine, who played 20 NRL games for Newcastle before he was released to join Canberra in 2016, carried the ball 203 metres and made 26 tackles for good measure.

The loss was Newcastle's 10^th in their past 12 games and left them needing divine intervention to have any realistic hope of reaching the finals.

With 10 games left in their season, the Knights are six points behind the top eight, but there are actually 10 teams who have banked at least three more wins than them.

The Raiders, in contrast, have won five of their past six. They are 11^th on the ladder but equal seventh in terms of victories.

Knights coach Adam O'Brien had mixed emotions after Sunday's roller-coaster ride, during which his struggling team fought back from a 14-0 deficit to hit the lead midway through the second half.

"They're pretty shattered in the sheds there, really disappointed and a bit of everything," O'Brien said.

He added that he was "really proud" of the way his troops rallied. "We had a never-give-in attitude towards the contest ... we showed a lot more of the resilience that I think we've lacked this season," he said.

He singled out skipper Kalyn Ponga, who overcame a stomach virus to play 80 minutes and create two tries, for special praise.

The Raiders dominated the first 40 minutes but Newcastle snatched a possible lifeline just before half-time.

Ponga ducked out of dummy-half, confused the defence, and threw a short ball that allowed Kurt Mann to dive over. Ponga converted, reducing Newcastle's deficit to 14-6.

Up until that point, it had been largely one-way traffic, prompting Foxtel commentator Michael Ennis to declare: "The Knights are self-imploding. They can't complete a set. Their attack is terrible."

Canberra led 14-0 after only 23 minutes through tries by Nick Cotric, Matt Timoko and Xavier Savage.

Newcastle's cause was not helped when representative forward Tyson Frizell suffered a head knock late in the first half and was forced out of the match.

Buoyed by their try on the stroke of half-time, Newcastle rallied after the break and looked set to post a courageous victory.

The game turned dramatically in the 55th minute when Raiders captain Elliott Whitehead was sin-binned for a late hit on Ponga.

In the ensuing set of tackles, Ponga grubber-kicked into the in-goal and bench forward Mat Croker scored, then Newcastle grabbed the lead with an Edrick Lee try in the 65th minute. The game hung in the balance until Young's moment of magic less than two minutes before full-time.