The final grand prix of the Ocala NSBA Summer Series saw a win for the US rider; Canadian Angela Covert was 9th riding Hollywood De Rase Z.
The American rider has enjoyed great success at World Equestrian Center-Ocala, and this marked his eighth Grand Prix victory.
The top 30 tackled Santiago Valera’s large and demanding course with Deslauriers picking up 13 penalties during his trip.
Deslauriers and the Holsteiner mare sailed around Santiago Valera's colourful Olympic course clear in the 5th-best time of the day.
The Jumping Individual Qualifier will take place on August 3, with the top 30 combinations moving on to the Individual Final.
The FEI Jumping European Championships Young Riders, Juniors, Children 2021 has wrapped up in Vilamoura, Portugal.
Saturday's feature Grand Prix at TIEC attracted a large international field, was interrupted by a storm and wrapped up Sunday morning.
Jumping looks set to be a testing thriller for many reasons, including how the three-rider no-drop-score format will play out.
Only three combinations qualified for the jump-off, but Moffatt ‒ who rode five horses in this class ‒ prevailed with Ariel Grange's stallion.
Canadian Tiffany Foster places 14th in the class with Northern Light, and also 2nd aboard Hamilton in a 1.45m class on Sunday.