Barclay Tagg (born December 30, 1937, in Lancaster, Pennsylvania) is an American Thoroughbred horse trainer. Tagg graduated from Pennsylvania State University with a degree in Animal Husbandry in 1961. Tagg is best known for conditioning Kentucky Derby, Preakness Stakes, and Jockey Club Gold Cup winner Funny Cide. Horses in Tagg's stable have included Tiz the Law, Showing Up, and Nobiz Like Shobiz. Formerly a steeplechase jockey, Tagg won his first race in 1972 at Old Liberty Park. He has been a journeyman trainer for many years and with Funny Cide became the first trainer to win the Kentucky Derby in his first attempt since Cam Gambolati with Spend a Buck in 1985. He won the 2020 Belmont Stakes with New York-bred Tiz the Law