Canadian Nicole Walker and Atout des Trambles were edged by Jessica Springsteen by just one-tenth of a second in the large class of 68.
The victory came aboard the mare Greya, deflecting a strong challenge from Christian Kukuk and his Olympic gold medal partner Checker 47.
This week the Belgian pulled out Katanga V/H Dingeshof, a speedy 15-year-old mare, for the first time this season.
The German rider won the lion's share of the $215,000 purse in the MARS Equestrian CSI4* Grand Prix on the grass field.
The Belgian rider won his second Cup round; Canadian Mario Deslauriers placed 7th riding S&L Quatro van de Meerputhoeve.
The Olympic champions took on a tough international field of 45 over Canadian Peter Grant's course, edging Ben Maher and Nina Mallevaey.
The grass derby field in Wellington saw 44 international entries compete over Olaf Petersen Jr's course, with the German rider duplicating last year's victory.
The 12 weeks of competition at Wellington International will feature the season finale $750,000 Rolex Grand Prix at the end of March.
Susan Pape and Harmony’s Eclectisch owned opening week of the 2025 Adequan Global Dressage Festival, taking the Grand Prix and the Special.
The Week 1 ‘Saturday Night Lights' at Wellington International marked the Egyptian rider's ‒ and his horse Ali's ‒ first win under the lights.