A sports writer for 55 years, Gillespie eventually carried BBWAA card No. 1, signifying seniority among active writers. He was with the St. Louis Star until it folded in 1951 and he became associate editor of The Sporting News. His biggest scoop was the $5,000 fine and indefinite suspension of Babe Ruth by Yankees manager Miller Huggins in 1925. Friendly with the Pasqual brothers of Mexico, he scored many inside stories when they raided ML teams to stack their Mexican League in 1946.