The 32-year-old, from Penistone, took the Tjade Collier-trained Ladronne to first place in a field of 26 for the pair’s first win under rules, beating Taras Day by a neck after coming up from last place.
Joe, who represented Great Britain in 2016, is the first member of the Whitaker dynasty to become a National Hunt jockey, with sister Ellen and brothers Tom and Donald all showjumpers.
Whitaker told Sky Sports Racing: “I just thought, ‘wait until the very last second and then give it some’.”