Rabbitohs fans have a park footy player they've never heard of to thank for delivering them an exciting young forward set to make his NRL debut this week.

Budding Souths back-rower Keaon Koloamatangi grew up in Bulldogs territory idolising Sonny Bill Williams and Willie Mason but has been a Rabbitohs junior since he was a kid thanks to his dad Izzy ā€“ with the pair combining to play for every single club in the South Sydney district.

The Mascot Jets junior laughs when asked by NRL.com how a kid from Burwood, which is near Concord just on the Bulldogs side of the Bulldogs-Tigers boundary, is South Sydney through and through.

"My dad played in the Souths comp for every other team except for Mascot," Koloamatangi smiles.

"He wanted me to play for Mascot because they always won! Instead of putting me in the Canterbury comp he wanted me in the Souths comp because he knew a lot of people, a lot of great players came from there."

From Benny Wearing and Eric Simms, to Bob McCarthy and George Piggins, to Mario Fenech and Ian Roberts, to Craig Wing and John Sutton, Koloamatangi snr has a point about the South Sydney district. His son ended up coming through the ranks alongside fellow Mascot junior Cameron Murray.

Rabbitohs back-rower Keaon Koloamatangi. ©Paul Barkley/NRL Photos

Izzy's influence on Keaon's footy journey extends, unsurprisingly, a long way past his choice of junior club.

"My dad always stuck by me and told me what the right thing was to do," Koloamatangi adds.

"Growing up he saw a lot of people take the wrong path and he didn't want me to take that so I'm really thankful for him helping me.

"There are tough times when you're growing up where your boys want to go out, want to party and you have to train the next day and it's a tough decision but at the end of the day you're doing something that doesn't feel like a job, it's unreal.

"He's strict but he's more of a best friend than a dad, I can tell him anything. He still gets excited when I tell him I'm playing this week. He gets more excited than me! He always records my games, always loves watching it, loves coming out. He's probably my biggest supporter."

So what will he be thinking when Keaon makes his NRL debut?

"I dunno man, he'll probably get a bit teary!" Koloamatangi laughs.

"He sort of knew I had the capability to become an NRL player but when you're 15 or 16 you see blokes like Jason Taumalolo and you think 'how am I going to tackle him?' But as you get older you get more confidence and when it starts to hit you your confidence gets bigger and you start to believe in yourself."

The NSW under-18s Origin rep was a handy rugby union player in his teens but says the 15-man game was never a serious lure given his love of league.

"I chose league about 13 or 14. I played reps for union too, it was a bit of a hard choice but I enjoyed league more," he recalls.

"Especially with Sonny Bill being my favourite player, I used to always watch him and want to be like him so I chose league. I played Harold Matts, SG Ball, everything Souths.

"Now to get myself my first top 30 contract is just a dream come true, even just training with the boys, shaking their hands, it's still pretty buzzy but it's starting to become a realisation now so I have to not back away from it and make the most of my opportunities."

Murray back to the middle to meet Storm front

Even though he did the NRL pre-season with the main Rabbitohs squad in 2018-19 as well, this year as a full-fledged teammate still took some getting used to.

"This year being in the top 30 it was easier to roll in but it's still pretty unbelievable," Koloamatangi says.

"You watch them on TV and now you're playing with them, it's unbelievable. I can't express it, it's pretty crazy."

Despite the retirements of John Sutton and Sam Burgess, Koloamatangi still has some big-name competition for edge back row spots following Murray's shift out wide and the likes of Jaydn Su'A and Ethan Lowe. Luckily for him Sutton is still around the club to hand out plenty of advice.

"Sutto still comes around and helps. Just the little things you don't really notice in a game that can make a really big difference," Koloamatangi says.

"They're the things that put you over the edge. I'm trying to crack for grade this year so that's what I'm trying to model my game around. I'm not really a person that looks up in defence and Sutto's really helped me because he's a ball player and I'm pretty good with my hands too.

"He always tells me when you reload, get back in attack, always look up and if there's an opportunity always take it. You're marked up pretty much against a half and they're smaller than you so you always take the opportunity because you can run over them or get a quick play-the-ball.

"He told me just back yourself. I've sort of lacked confidence growing up so they're always telling me 'you can run over people, you've got mad footwork'. That sort of stuff really helps build my confidence."

Storm v Rabbitohs - Round 4

Koloamatangi admits he had some nerves heading into the NRL Nines and his team's first trial against the Eels having not played since a shoulder injury that required surgery last June.

While some players can be very superstitious about sharing their personal goals, Koloamatangi is forthcoming.

"It was a little goal for me I wanted to achieve, make the Charity Shield and make the Nines, which I did," he says.

"I normally put a vision board together, little micro goals I like to do. I have a big picture which is to make my NRL debut but my little goals are things like trying to get through pre-season injury free, try and drop some weight, be disciplined on my diet, stuff like that. Just work my heart out and see what happens."

Told of comments from his senior teammates, including Damien Cook, that he was a player they expected to see debut sooner rather than later, Koloamatangi ā€“ who is relaxed and chatty throughout his interview with NRL.com ā€“ is momentarily speechless.

"Wow," he says. "That'sā€¦ that's pretty humbling, hey. You don't really expect that.

"They've played NSW and stuff like that. Coming from the senior boys it means a lot. Obviously they're looking at me knowing they can trust me. It really gives me a lot of confidence that they can trust me and I can play my own game and know they'll have my back so it's really good."