He quit league to follow his passion for boxing in 2000, the same time as friend Anthony Mundine. Mundine, who made his pro debut on the same card and went on to have a successful career, reckons Haumono can surprise Parker.
"I texted him when I found out he got the fight against Parker, because I know how big this is, the biggest of his career," Mundine told the Daily Telegraph recently. "His response to me was, 'I'm going to take him to dark places'.
"Now I don't know what that meant, but I definitely don't want to be going to dark places with Sol. If you don't know the brother, and he says he wants to take you to a dark place, you definitely aren't going anywhere good.
"Sol is in with a big chance, simply because of his sheer power and belief in himself. The one thing I know about Sol is that his desire to be a world champion goes back a long way."
A victory for Haumono against Parker would be a huge shock and would pave the way for a shot at Anthony Joshua's IBF heavyweight title.
Parker represents the highest quality opponent Haumono has faced in his 28 professional fights, of which he has won 24, but while trainer Justin Fortune has said his man is in the best possible physical shape, the occasion is a big one for someone who appeared overawed in his last fight against lowly Argentine Manuel Alberto Pucheta.
Haumono has been angling for a fight against Parker for some time. Now he gets his chance in what is likely to be the biggest pay-day of his career, quite some achievement given where he was a few years ago.