There will be a plethora of top 100 pro triathletes on show at IRONMAN New Zealand in Taupo on Saturday.

The likes of Fenella Langridge, Alanis Siffert, Pieter Heemeryck and Joe Skipper are all taking part.

However, there will be another household name making their IRONMAN bow at the weekend as former New Zealand international rugby union star Liam Messam takes on the mammoth challenge.

Olympian and World Cup winner

The 40-year-old former All Black enjoyed an incredible career, competing for his country in both the 15-a-side game and Sevens.

He made 43 international appearances for the Kiwis and was part of the 31-man squad that won the 2015 World Cup in England.

Messam also represented his country at the 2006 and 2010 Olympic Games in the Rugby Sevens competitions, claiming a pair of gold medals.

Following his retirement from rugby union, Messam has dabbled in professional boxing and boasts a 7-1-1 record, with one victory by knockout.

Taupo challenge

Not satisfied with excelling as a rugby player and a boxer, Messam has now turned his attention to triathlon and is set to complete his first full-distance race, which in Taupo will feature a 3.8km swim starting and finishing on the shores of Lake Taupo, a 180km ride taking in the rural landscapes of the region, and a 42.2km run along the lakefront.

“I think the guts of it is that I really want to test myself mentally and physically,” he said in a statement released by IRONMAN and published by the NZ Herald.

“I love training, I love training hard and also with my boxing and rugby I’ve always pushed myself in the trenches and I love to go deep and really mentally push myself.

“Then one day I just was watching a half Ironman and I saw the pros go past and I was super impressed with just how fast they were running, they’re pretty much sprinting, and then I just saw your everyday person start coming off their bike and trying to walk and I just thought, this is it.

“And then from there I got on to some people I know, and here we are today.”

The Kiwi star has two ambitions for this weekend’s race:

“I just want to get through it and just complete the whole thing. It’ll be a massive achievement because it’s a long day.

“But I have also heard that you catch the IRONMAN bug 20m out from the end of the race. I’ll be making sure I have my fly spray and my fly swat to make sure I don’t catch any IRONMAN bug.”

It seems it could be a one and done for the former rugby international, at least over the longest distance in the sport.