Twelve came back for round two, with all but McVean carrying faults. It wasn't until the final two that there came another clear round - this time from Australian Brook Dobbin aboard the lovely big grey Advisor.
It was down to McVean - if she dropped a rail, she would force a jump-off.
"She just tried her little heart out," said McVean of 11-year-old Daffodil, who is a half-sister to superstar Dunstan Delphi, on whom she won the Olympic Cup in 2010.
The Aussie visitors took more than their fair share of the top prize money, with Dobbin second, Evie Buller on Yalambi's Landor third and Paula Hamood and Nero GHP fifth equal.
Kiwi Olympians Maurice Beatson (Dannevirke) on the perennial My Gollywog was fourth with Daniel Meech (Taupo) and Carlotta fifth equal.
McVean and Daffodil, along with Dunstan Zimoreana G will head to Australia in just over a week to compete at the Sydney Royal and a couple of World Cup shows.
McVean steered Dunstan Kiwi Iron Mark (owned by June Berrington) to victory in the Seven Year Old of the Year class. Iron Mark was owned by the late Melanie Purcell, who at just 24 years old died of cancer. McVean is riding the horse for Purcell's mother June Berrington.
Results:
Showjumping, Olympic Cup: Katie McVean (Mystery Creek) Dunstan Daffodil 1, Brook Dobbin (Australia) Advisor 2, Evie Buller (Australia) Yalambi's Landor 3, Maurice Beatson (Dannevirke) My Gollywog 4, Daniel Meech (Taupo) Carlotta (owned by the Burnett-Grant family) and Paula Hamood (Australia) Nero GHP =5.
NZ Speed Horse of the Year: Megan Stacey (Te Puke) Shimmer Man 1, Megan Webb (Hunterville) Abernaki Chief 2, Katie McVean (Mystery Creek) Dunstan Zasjany D 3, Anna Stephen (Martinborough) Constantine 4, Vicki Wilson (Kerikeri) Showtym Girl 5, Amanda Wilson (Whangarei) Showtym Viking 6.
Seven Year Old of the Year: Katie McVean (Mystery Creek) Dunstan Kiwi Iron Mark (owned by June Berrington 1, Kim Best (Otane) Giggles 2, Katie McVean (Mystery Creek) Dunstan Springfield 3, Daniel Meech (Taupo) Branson MVNZ (owned by Garry Hogg) 4, Phillip Steiner (Tauranga) Annandale Renaissance NZPH 5, Oliver Edgecombe (Waipukurau) Cortaflex Burttorio 6..
Eventing, CIC***: Annabel Wigley (Amberley) NRM Frog Rock 1, Donna Smith (Te Kauwhata) Henton Executive 2, Abby Lawrence (Te Puke) Pseudonym 3, Donna Smith (Te Kauwhata) Balmoral Sensation 4, Juliet Wood (Whangarei) Bold Trader 5, Annabel Wigley (Amberley) NRM Enzo 6.
Trans Tasman Squad: Simon Gordon (Auckland), Fletch.com and Simply Mitch; Christen Hayde (Pukekohe), Tandarra Sweet As; Brent Jury (Rangiora), SE Big; Abby Lawrence (Te Puke), Pseudonym; Donna Smith (Te Kauwhata), Henton Executive; Joe Waldron (Australia), Springvale All Black; Annabel Wigley (Amberley), NRM Enzo and NRM Frog Rock.
Dressage, Horse of the Year: Louisa Hill (Clevedon), Bates Antonello 1, Nicky Pope (Whitford), Fabarchie 2, Hannah Appleton (Nelson) Fiber Fresh Zactac Graceful 3, Bill Noble (Hamilton), Airthrey Highlander 4, Kieryn Walton (Taumaranui) Saraceni 5, Christine Weal (Te Awamutu), Spielzeit 6.