Collins was commissioned to paint more than seventy-five of the leading racehorses of her time, including Citation, commissioned by Nat Herzfeld former President of Tropical Park Race Course, Chrysler II and By Jimminy for Walter P. Chrysler, Dom Bingo for Bing Crosby, Tom Fool for Jock Whitney, and Discovery and Bed o'Roses for Alfred Gwynne Vanderbilt, Jr.