McCormack is a three time winner of the Hawaii ironman event but has spent the past year back on the ITU circuit as he tries to book a place at the London Olympics. He's using Kinloch to search for more of the leg speed required to compete over the shorter distances.
The ITU Oceania sprint title and valuable ITU points are up for grabs and Gemmell is keen to be at the head of the pack in the 750m swim, 20km bike and 5km run.
"I have won the standard distance nationals five times but never won the sprint title at the elite level,'' he said. "It is something I like doing and have spent a good part of my career doing this type of race in Europe racing in club competitions and I always enjoy Takapuna each year over a similar distance.
"But there is a big contingent of Australians coming over chasing those ITU points so it won't be easy and the course at Kinloch is a tough one. Racing over this short distance hurts, too. There is no letting up from the gun with a nasty hill on the bike so I'll be looking to force the issue there. My aim is to place as much pressure on the field as possible on the bike and come off with a bit of a lead and sort ourselves out over the 5km run.''
In the women's race, McIlroy, Tanner, Samuels and Teresa Adam head the Kiwi contingent up against a strong Dutch team and a horde of Australians.
Tanner had issues with her running last season and has been working hard in the off season for another Olympic campaign after she finished 10th in Beijing in 2008. After some time off, it has been hard work in training towards that goal.
"For me, racing in January is a bit different,'' she said. "I haven't raced the New Zealand season in a long time as I am usually in a big base phase but, with Olympic qualifying in April in Sydney this year, I need to be fitter and faster sooner.
"We are still clocking up some big miles but I'm going into a little taper this week for Kinloch, with it being the Oceania sprint champs.
"Everything I do right now is focused towards Sydney, all these Contact sprint races and then the standard distance racing is part of a pathway to Sydney and qualifying for the Olympics. That is our last chance to qualify so that is really the goal.''