Gallen couldn't find the knockout blow that NSW fans at The Aware Super Theatre were baying for on Wednesday night.

But the former Blues warrior still packed too many punches for his long-time former Queensland adversary, awarded the contest 60-54, 60-54, 59-55 by the three judges.

"He broke my heart plenty of times, Hodgo, so it was good to get one back at him but he's a warrior," Gallen said.

"He's got power. I wasn't prepared to take too many risks tonight so I just did what I needed to do, used my jab.

"But I got the win and not too many people get to go out on a victory, especially in boxing so it was good to do it tonight.

"I'm just glad it's all over - I've had enough. I'm 41 going on 42. You've got to slow down at some stage and it's hit me now so it's time to pull the pin."

Gallen leaves the ring with an impressive 15-2-1 record, with his only defeats coming against Justis Huni and Kris Tervieski for the Australian heavyweight title.

He gallantly went the distance in both bouts, only to lose on points.

While a courageous victory over UFC legend Mark Hunt and a stunning first-round knockout of one-time WBA heavyweight champion Lucas Browne were the highlights of his pugilistic career, Gallen ranks going toe to toe with Huni as a stand-out memory.

In rugby league, the ironman achieved more than most players could dream of.

Gallen captained Cronulla to their one and only NRL premiership in 2016, NSW to a drought-breaking State of Origin series win over Queensland in 2014 and also won a World Cup in 2013 during 32 Tests for Australia.

One of the toughest players ever to lace on a boot, Gallen, after this week claiming to have grossed $25 million in the past three years, is unfazed about the physical toll the game took on him, despite brain trauma affecting a swathe of retired greats.

"It's part of life. What can I do about it? I've played over 400 games of rugby league. I've had 15 or 20 fights," he said.

"What's the point of worrying about it? This CT (issue), all that sort of stuff, I'm not trying to downplay it but you don't find out about it until you're dead anyway, or you don't know til you're dead.

"I've got a wonderful family, a beautiful wife. I'm loving life. I'm in a good place financially. I don't need the money any more so what's there to worry about?

"Whatever comes up in the future, comes up and I'll deal with it then."

Australian Associated Press