Making the win even more special was the fact that dad Jeff won the very same class on Delphi's dam Flower Power in their first world cup start together 12 years ago.
Twenty-three-year-old Olympian Katie McVean and Delphi were the only one of 12 combinations to go double clear over the Kevin Hansen designed course.
"Delphi jumped well in her first two star grand prix at Gisborne last weekend, so we decided she was ready to step up to this level - she did it without any trouble at all," she said.
McVean also finished fifth on her Olympic horse Dunstan Forrest II.
Despite making the Olympics and winning all sorts of other top awards in recent years, world cup wins have eluded McVean since her first season competing in them when she was 18. This was just her third world cup round win. It's been a while since McVean won a world cup round - years actually. The only other two rounds she has won were in her first year competing in them.
Later in the season McVean will bring out the newly imported stallion Corofino II.
Settling for second and third respectively were Simon Wilson (Waipukurau) on Right Royal and another former Olympian Maurice Beatson (Dannevirke) on Zibibbo who were all clear in the first round but dropped a rail each in the second, with time deciding the placings.
Fourth was 2008-2009 series winner Anna Trent (Hawke's Bay) on Cortaflex Levitation NZPH, with Air Hill the Rajah, who is also a previous series winner, in sixth place in the hands of new rider Julie Davey (Hastings).
Course designer Kevin Hansen (Hawke's Bay) made it clear he would be building a big, challenging and technical course, and he didn't disappoint.
The New Zealand series will be run over nine rounds, with the final two in Gisborne in late January 2010, including a speed round. A new indoor round at Manfield Park in Feilding in the evening of December 12 will add a new spectacle to the series.
A large field will be expected there as any series winner who plans to represent the country at the world final must have competed in the indoor round. The world final will be held in Geneva, Switzerland, from April 14-18.
In the young rider class Bridget Hansen (Hawke's Bay) is stamping an early mark on the series. With just a handful of starts to her credit she won the class in Hawke's Bay on Cortaflex Monamie NZPH and placed third on Cortaflex Oceanbeach NZPH.
Maurice Beatson (Dannevirke) totally dominated the horse grand prix taking the trifecta with Jedi Warrior, Once a Warrior and Kiwi Relic.
Katie McVean (Mystery Creek) Dunstan Delphi 1, Simon Wilson (Waipukurau) Right Royal 2, Maurice Beatson (Dannevirke) Zibibbo 3, Anna Trent (Hawke's Bay) Cortaflex Levitation NZPH 4, McVean (Mystery Creek) Dunstan Forest II 5, Julie Davey (Hastings) Air Hill the Rajah 6.
Toyota Young Rider: Bridget Hansen (Hawke's Bay) Cortaflex Monamie NZPH 1, Rachel Bentall (Hastings) Kiwi Brave 2, Hansen (Hawke's Bay) Cortaflex Ocean Beach NZPH 3, Helen Bruce (Palmerston North) Dark Magic 4, Rachel McGregor (Auckland) Kabo Benny Boy 5.
Horse grand prix: Maurice Beatson (Dannevirke) Jedi Warrior 1, Beatson (Dannevirke) Once a Warrior 2, Beatson (Dannevirke) Kiwi Relic 3, Anna Trent (Hawke's Bay) Cortaflex Nicalette 4, Catherine Cameron (Cambridge) Vespera SL 5, Jason Ellmers (Pongoroa) Millie's Wish 6.
FMG pony grand prix: Jake Lambert (Matamata) Once in a Blue Moon 1, Luke Dee (Gisborne) Maximus 2, Logan Massie (Dannevirke) Kickin the Clouds 3, Alexa Randall (Auckland) Millbrook 4, Dee (Gisborne) Condoleezza 5, Randall (Auckland) Starlight Express 6.