St George Illawarra Dragons young gun Steven Marsters hasn't put a time frame on it, but one day soon plans to take out one of his own in the NRL.

Marsters is the cousin of Esan – the Wests Tigers centre coming off a huge second season of NRL that saw him rewarded with New Zealand Test honours.

Despite being three years Esan's junior, Marsters said he is constantly attempting to one-up his cousin no matter the circumstances.

The two-time Junior Kiwis representative is currently undergoing his second full pre-season at the Dragons.

The 19-year-old was expected to see out the 2018 season in Jersey Flegg but ended up playing double the Intrust Super Premiership games than he did in the Under-20s.

"It would be a dream come true to play Esan in the NRL. Our grandad always told us that if we were to ever play each other to take off each other's heads," Marsters laughed.

"Esan and I love going at one another. Every time a family barbecue rolls around, you'll find us in the backyard going at each other.

"We try and beat one another at everything. If we're playing golf or tennis we'll be taking it seriously. It'll always end up in a fight.

"I have always wanted to play better than him and be better than him which is exactly how he looks at me. Our whole family sees that."

Friendly fire aside, Marsters's biggest influence is his older cousin.

Esan made his debut for New Zealand at June's Denver Test against England and has since represented the Kiwis five times.

The sight of Esan donning the black-and-white jumper for the first time left little doubt in Marsters' mind who he aspired towards.

"Seeing him go through all the hard yards as a kid to what he's achieving now, it makes me proud. When I saw him put on his first Kiwis jersey, I cried. That's how special Esan is to me," Marsters said.

"Esan has been my biggest influence. Everything that I know now is because of him. Seeing where he is now, it has played a huge role in my life.

"Watching him play for New Zealand over in the UK recently, and also against Australia, was a huge moment for me as well."