Thirroul captain-coach Nathan Fien already has an NRL premiership ring and a World Cup winners' medal, but he declared an Illawarra Coal League title would take a very special place alongside them if the Butchers win on Sunday.

Few milestones eluded him in his 14-year 276-game top-grade career, but Fien said swapping the high-profile NRL for the suburban charm of Gibson Park would bring a very different sense of achievement if he can get the Butchers over the line.

"I guess last year when I left the NRL I was able to reflect on my playing career and I ticked a few things personally and achieved everything I really wanted to," Fien said.

"But to be able to give back to rugby league by not just coaching but also playing for a side like Thirroul it's been fantastic.

"I've been welcomed right from day one and the boys have bought in to everything I've tried to achieve.

"We've had the emergence of guys like Sam Clune - he's been a revelation this year - and Sammy Coster who has been tremendous for us.

"We've been able to bring through a lot of young kids like Jay Gallagher, Andrew McCarthy and Lee Higgins, who've gone into the [Dragons] 20s, so looking back on the year being able to have an impact on guys like that ... it's what footy's all about and I think that's what I'll be most proud of."

While he hasn't had to "re-invent the wheel" Fien has certainly put his stamp on the club which - right from a grinding 12-8 victory over Collegians on a sodden pitch in round one - has exhibited all the traits of the coach.

It's a tough style off football that's seen the Butchers win every tight match en route to the decider, including a 19-18 golden-point victory over the Tigers in the major semi-final.

"To be honest that team spirit that needs to be there to win footy games is already well ingrained in the Butchers footy club," Fien said.

"We all just play for each other, that's probably the key. You've got to go out and earn it week in, week out and we've been able to do that and produce that throughout the year."

It's an attitude that's got them through plenty of tight ones, but Fien said it will amount to nothing if they fail to reproduce the same grit and poise against a Tigers side with a burning desire to expel the demons from their close loss in last year's grand final.

"Helensburgh have given us some tremendous battles throughout the year. We've played four times and up until last week we were one win apiece and a draw, so it's very hard to split the sides," Fien said.

"Luckily we were able to get the job done in the major semi but it was by the slimmest of margins and I don't see anything changing there. It's going to be a tough encounter and it could be another 80 or 90 minutes to see who's going to be the victor on Sunday."