Britain’s Scott Brash and Intertoy Z beat Olympic champion Eriz Lamaze into second place to scoop the lucrative $50,000 ( £32,000) Wellington Equestrian Realty Grand Prix in Florida.
Twelve of the 50 entries went clear to go through to the jump-off.
Meredith Michaels-Beerbaum set the pace at 42.16 seconds – but Scott and his father Stanley’s Intertoy Z shaved more than two seconds off her time to stop the clock at 40.02.
Canada’s Eric Lamaze was second on Derly Chin de Muze with Katherine Dinan of the USA and Vancouver second.
Scott, 26, said the big ring at Wellington Equestrian suited Intertoy.
“He is a big, slow jumper but he was fast tonight. The big ring suits him.
“It wasn’t an overly big course but it is nice not to have to jump big every single weekend,” he added.
Scott has partnered the 13 year old Zangersheide geldeing by Interadel Z since he was a five year old.
He is one of several British riders who’ve decamped to Florida for the three-month FTI Consulting Winter Equestrian Festival.
Nick Skelton has already notched up wins with Carlo and Unique.