It's literally been the case for Wollongong slugger Tonga Tongotongo who'll swap the footy boots for gloves this weekend.

Normally a hard-running back-rower for the Corrimal Cougars on weekends, Tongotongo will step into the ring for the first time as a professional against Queenslander Rob Barron.

It comes with the ringing endorsement of Gallen, with whom Tongotongo has shared countless sparring rounds with the Cronulla premiership-winning skipper over the past two years.

Watching what Gal's managed in the squared circle in that time has left Tongotongo confident he can make the pro ring home.

"I've never been pressured like that in my life," Tongotongo said of the sessions.

"Usually I'm the one putting all the pressure on but as soon as Paul Gallen got in there it was like a huge mountain just staying in front of me.

"I just had to try and throw as many punches as I could and get away. It wasn't until the last time we sparred I got a decent body shot on him and it was the first time he stepped back for a second.

"Then he was right back on me and I had to run again. It was really good sparring and it gives me big confidence and big respect for him as well.

"Not many people have mixed boxing and rugby league at the same time but watching him I just thought why can't I do it?"

Having won three straight amateur bouts by stoppage, Black Diamond head coach Steve Psaras said the time was right to make the pro jump; with Gallen offering his endorsement.

"Last time Paul came down here for sparring they both rocked each other and Gal turned to me and said 'turn this guy pro immediately, he's wasted in the amateurs'," Psaras said.

"They've done lots of rounds many times, he's an absolute gentleman.

"Cold [knockouts] in the amateurs just do not happen and he's knocked the last three out. We understand it's amateurs, but this is business now.

"We've got him scheduled to fight in four weeks time up in Sydney and then another one back here at Waves on July 30 so we'll be getting him in there every four weeks.

"It's good start for him and I'm sure he's going to put on a show."

It was to be the feature attraction on a 10-fight Black Diamond Boxing fight card at Towradgi Beach Hotel but will now share top billing with two regional title bouts.

Read more: Freestyle MMA opens doors to new challenge

The added bouts will see 6-1 welterweight Michael Pengue take on J Sabari over 10 rounds for the WBC Australasian title, while Bondi Boxing Club stablemate Mirko Pizzi will face Wasan Srihongsa for an ANBF title over eight.

The card will also see nine amateur bouts, including Black Diamond Boxing trainer Emmerson Tull in the feature amateur bout, taking on Elodie Anna for the NSW light-welterweight (59kgs) title.

"Emmerson's fighting for the light-welterweight state title so she's the headline amateur," Psaras said.

"She's been amazing this prep, she's coming off two really good wins and I'm confident she'll bring this one home. It's the first time she's done a four-rounder so it's good to see her go four twos.

"She's one of the coaches here and she has a hug following already. We've also got Lauren Gavin, John Hill, Naya Clarke and Zeke Latini fighting.

"Zeke's 16 but he's got approval to fight up in the elite level against a 19-year-old Sonny Knights who's a two-time state champion, so it's a big litmus test for him.

"It'll be pretty good to put on a show for everyone in Wollongong."

The card will also mark Dragonfit Fight Club's return to the fight game, with Brad Gallagher returning to former NRL hardman Josh Miller's Dragonfit gym.

Gallagher has taken on coaching duties with fomer pro Brad Viegel, while Miller will handle the stable's strength and conditioning, wit Matthew Mccance (77kgs) and Jake Warby (72kgs) repping the gym on Saturday's card.

"Jake's been with me two years but it's been six months since he's gone into [competitive] boxing and he's going really well," Gallagher said.

"He's the guy that really wanted to make train fighters again because he wanted to get in there and fight. Matt's been great too, he will be a pro within year.

"They've made me love boxing again and we're back at Dragonfit with Joshy Miller and we're building that fight gym again. They've both got a bit of a future in it if they stay on the right path."

Download the Illawarra Mercury news app in the Apple Store or Google Play.

Sign up for breaking news emails below ...