But that's exactly what the Cowboys workhorse will do when he laces up the boots to face the Melbourne Storm at ANZ Stadium on Sunday night.

It's a return to the game's biggest stage nine years in the making after Fensom guided the Canberra Raiders to the first under 20s premiership in 2008.

Fensom was Canberra's skipper on that day but the success never translated to the NRL - his only other taste of grand final day was as a spectator a few years ago.

In fact, the thrilling under 20s decider remains the only grand final Fensom has ever won.

But a move north of the border has landed him on rugby league's biggest stage and he'll get another rock star reception at Townsville airport if he can help stop the Melbourne juggernaut.

"I went to one maybe three or four years ago just as a spectator. I have watched one in the stands and it's a pretty big occasion," Fensom said.

"It has [sunk in] but it stills feels very surreal. I'm sure the feeling is going to grow more towards the end of the week.

"I'm just going to take the weekend and just soak it up, and just enjoy the moment and the occasion."

Fensom's last game as a Raider was also a grand final - he played for Mounties in their NSW Cup defeat last year.

Raiders captain Jarrod Croker played a huge role in Canberra early under 20s success and played alongside Fensom for the best part of a decade.

Croker quickly learnt Fensom is "as tough as they come" and says "he hasn't changed one bit on and off the field" since he lifted the under 20s trophy.

"He was always one of those blokes who would bust his backside for everyone that was playing with him. I know nothing has changed since then," Croker said.

"Off the field, he's just a laid-back bloke, a knockabout bloke who is the ultimate professional. He plays the majority of his footy busted or with something wrong with him.

"He's a great friend of mine, Fenno. I'd love nothing more than to see him win a premiership ring and lift that trophy again.

"We played footy together for basically 10 years and we've been great mates that whole time. I still keep in contact with him now and I know a lot of the boys do.

"He's a good mate of everyone's, a club favourite and a fan favourite in Canberra. He's always had a place in our hearts, that's for sure. It would be great to see him get that ring on Sunday."

The 28-year-old found out North Queensland were keen to secure his services and "two or three days later" he was training in the Townsville heat.

They were 17 minutes away from missing the finals but earned a late reprieve, so the Cowboys put the beers back in the fridge and their never-say-die attitude is behind an unlikely charge to the decider.

They're doing it without big guns Johnathan Thurston and Matt Scott, which Fensom says proves just how good the Cowboys are.

Cowboys playmaker Michael Morgan has "got the ball on a string" and playing alongside the "incredible" Jason Taumalolo has Fensom on the cusp of a fairytale premiership.