The former Australian sevens star will return to the 13-player game after nine years of rugby union, having previously represented the Jillaroos as a teenager.

In that time, Tonegato developed into one of the most lethal finishers on the sevens circuit, playing a crucial role in Australia's historic gold medal at the 2016 Olympic Games.

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Tonegato flirted with the idea of playing NRLW in 2020, the speedy back almost signing with the Roosters after the Tokyo Olympics were postponed by a year.

It was a path pursued by Australian teammates Charlotte Caslick and Ellia Green, however the 26-year-old decided to focus on her studies and pursuit of a second gold medal.

The women's sevens side experienced a disappointing fifth-placed finish at the rescheduled Tokyo Olympics, Tonegato admitting to the Mercury her future was uncertain after returning home.

Approaching the end of an occupational therapy degree, she has decided the time is right to step away from rugby union and look forward to the next phase of her life.

"I'm super excited to be a part of the Dragons, it's a great club and has a strong history in Wollongong,"Tonegato said.

"My career started in rugby league here in Wollongong, I played for the Helensburgh Tiger Lillies and ended up being selected for the Jillaroos from there.

"I've always wanted to see how I'd go playing in the NRLW especially since it wasn't around when I started playing. I'm looking forward to seeing how I stack up against the other girls."

Tonegato joins a St George Illawarra side that will be led by captain Kezie Apps and new coach Jamie Soward.

Club officials are in the process of finalising the squad for the delayed competition, with 17 players currently signed.

It's a group that includes local juniors Keeley Davis and Teagan Berry and 2020 Dragons player of the year Shaylee Bent.

St George Illawarra general manager of football Ben Haran said Tonegato will bolster an already talented squad.

"The opportunity to bring someone with her experience across both codes is a big addition to our NRLW squad," Haran said.

"Her history playing rugby league within our region is a really great story for our young aspiring female players throughout our pathway systems.

"To secure a player of her quality and experience with ties to the region is certainly a positive and the club will only benefit from the arrival of Emma."

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