Into the home straight for the final time it was McIlroy who proved strongest, pulling away in a great display of strength and leg speed, especially for so early in the season.
"I'm really happy, it was a really hard race, we pushed the whole way," McIlroy said. "The bike was aggressive and on the run there was a group of us pushing the whole way. Team tactics didn't come into it at all; I think we all had a plan of trying to bike really hard and keep the chasing group away from us and maintain that gap.
"Once on the run the pace was on the whole time, Danne went out quickly so there was no time to rest. There were a few surges on the last lap from Rachel, I made sure I stayed with her the whole time and got ready for the sprint, it isn't the strongest part of my racing but I managed to find enough today."
The Dutch have spent the summer training in New Zealand under the watchful eye of former New Zealand coach John Hellemans, now running the Dutch national programme.
That work under the eye of triathlon legend Hellemans is paying dividends with Klamer finishing second to Andrea Hewitt in Wanaka and now a close second to McIlroy and in doing so, taking out the under-23 race category.
In the men's race drama struck favourite and winner at the ITU World Cup race in Auckland last November when Kris Gemmell retired due to mechanical failure on the bike. Gemmell's derailleur broke, bringing his race to an abrupt end.
It was Australian Royle who went one better than his runner up finish at the 2011 Oceania standard distance championships in Wellington, winning comfortably from a chase group that included New Zealand's Martin van Barneveld.
Royle rode superbly, exiting onto the run alongside Tom Davison (Christchurch) and Edward Rawles (New Plymouth), the two Kiwi youngsters riding superbly in elite company. The third-seeded Aussie held on in front of fast finishing Jan Van Berkel (NED) and Jamie Huggett (AUS), with Van Barneveld in fourth in his first race since Beijing last year.
Van Barneveld took the New Zealand championship honours as the first Kiwi in fourth place, a result all the more meritorious given it is his first race for almost 5 months.
Under-23 and under 19 titles were also on the line with strong fields assembled in all races categories.