Sonny Bill Williams can fill the gaping hole in his impressive sporting resume on Saturday by leading New Zealand to a repeat triumph over great rival Australia in the Rugby League World Cup final.
Since 2009, Williams has flitted between rugby union, boxing and league - and success has followed him everywhere.
He is New Zealand's top heavyweight boxer after winning all six of his fights, captured World Cup and Super Rugby titles in the 15-man code and this year claimed the NRL title with Sydney Roosters at the end of his first season back in league.
And after being voted as rugby league's International Player of the Year for the first time on Wednesday, Williams said winning rugby league's biggest prize three days later "would definitely top everything off."
"To come away and enjoy time over here with the brothers and put that Kiwi jersey on, for myself I have actually fallen back in love with rugby league this year," said Williams, who is bidding to become the first player to win World Cups in both rugby codes.
Even with Williams on board, New Zealand heads into the game at Old Trafford, the home of England football giant Manchester United, as the underdog.
Australia has not been beaten in its last six meetings with New Zealand and has cruised into the showpiece match, conceding just two points and scoring 210 in its last four games since beating co-host England in the tournament's curtain-raiser.
New Zealand, meanwhile, was seriously roughed up by England in an epic semifinal at Wembley Stadium but still came through after scoring a converted try with barely 20 seconds left to win 20-18.
"Twelve rounds?" said Williams, the part-time boxer. "It certainly was like that."
The Australians have bristled at suggestions they will be undercooked going into a match they have waited five years for - since losing 34-20 to the Kiwis in Brisbane in the 2008 final.
"We've played Fiji twice, they are a big physical side and when it's all said and done they finished the fourth best team in the tournament," said Australia coach Tim Sheens, referring to his team's 64-0 win over the Islanders in the semifinal. "The score line just doesn't indicate how much ice was on the guys after the game, I can tell you.
"What I was very happy about was that we kept the pedal down for 80 minutes. We didn't drop off, and haven't in the tournament. Preparing for the final, we wanted to play the 80 minutes and we have done the whole month. I am hoping that intensity prepares us well for what will be the most intense game of the tournament."
Like Williams, Australia's star players won't be short of motivation, either.
Johnathan Thurston, Cameron Smith and Billy Slater, who appears to have overcome a knee injury sustained in the quarterfinal win over the United States, all turned 30 this year and are unlikely to be around for the next World Cup in 2017.
This may represent their last chance to get their hands on the World Cup, a feat they haven't achieved amid stellar careers in the NRL and with Queensland.
"For us, it's an opportunity to win a World Cup - we don't look at it as a last opportunity," Australia captain Cameron Smith said. "And we don't see it as a chance to make up for what happened in 2008. Nothing will ever make up for that.
"When our career comes to an end, we aren't going to look back and judge it off one match, one result. We'd like to think we've done a fair few things in our career over multiple matches that people can look back on."
Australia is looking to win the trophy for a record-extending 10th time in 14 World Cups.
"Obviously we are the reigning world champions but in the past four years they haven't lost too many games," Williams said. "Australia definitely set the standards."