Born in the small town of Houcktown, Ohio, Hoy became deaf after suffering from meningitis at age three. He graduated from the Ohio State School for the Deaf in Columbus as class valedictorian. He opened a shoe repair store in his hometown and played baseball on weekends, earning a professional contract in with an Oshkosh, Wisconsin, team which was managed by Frank Selee in 1887. In 1888, with the Washington Nationals of the National League, Hoy became the third deaf player in the major leagues, after pitcher Ed Dundon and pitcher Tom Lynch. In his rookie year he led the league in stolen bases (although the statistic was defined differently prior to 1898), and also finished second with 69 walks while batting .274. At 5'4" and batting left-handed, he was able to gain numerous walks with a small strike zone, leading the league twice and compiling a .386 career on-base percentage.