 Sent to race in the United States, he won the Grade III Broward Handicap at Gulfstream Park in Hallandale Beach, Florida, over 1700m by five and a half lengths.During his preparation for the Grade I Donn Handicap, Horse Chestnut fractured a piece of his splint bone on his near foreleg, resulting in his early retirement from racing.The Oppenheimers subsequently sold the majority of shares in Horse Chestnut to Seth Hancock's Claiborne Farm in Kentucky, where he went to stud.