Manu Vatuvei says the butterflies this week are similar to those he felt before his two biggest NRL matches.
The Warriors winger is preparing to enter the boxing ring with Olympic rowing champion Eric Murray in Auckland on Saturday night in the Fight for Life charity event for prostate cancer awareness.
"My nerves are the same as before the grand final and my first game for the Warriors," he said.
"It's a good thing, though. If you're not nervous, then there's something wrong."
The combination of the Warriors' tough pre-season and training for a bout of three two-minute rounds has given Vatuvei's giant frame a sleek look.
The player nicknamed The Beast said he was down to about 106kg, 6kg lighter than his published playing weight last season.
"It has been a massive help, especially with all the running we're doing at the Warriors," he said.
"I can last a bit longer and still think under fatigue."
There was more smiles than steely stares when Vatuvei, 26, and Murray, 30, faced off for the photographers at a press conference on Wednesday.
"He's an awesome guy and I totally respect him," Vatuvei said.
"I loved watching the Olympics and he's a national hero for New Zealand."
Neither Vatuvei nor Murray was into making a prediction, both saying anything could happen in a boxing ring.
Murray, who with Hamish Bond won gold in the men's pairs at the London Games, is hoping his base fitness from rowing will give him an advantage.
He said he had always had an interest in boxing, and its individual nature was a big change from the team focus in his own sport.
While his face-off with Vatuvei was good natured, he said he was serious about the bout.
"I don't like losing," said Murray, who hasn't tasted defeat in the men's pairs since he and Bond joined up four years ago.
Other rugby league stars fighting on the night include Willie Mason, Paul, Gallen and Greg Bird.