Forsythe was a standout football player at right guard for Clemson Agricultural College in Clemson, South Carolina, playing for three years under coach John Heisman, from 1901 to 1903. Heisman's Clemson Tigers football teams finished 3–1–1, 6–1 and 4–1–1 during those seasons, claiming southern championships in the latter two, and Forsythe started in each of those games. Moreover, he played every minute of those eighteen games, providing a remarkable example of athletic stamina and resilience. As was typical in the early 1900s, Forsythe played both offense and defense. Teammates on the line included Vet Sitton, Hope Sadler, and O. L. Derrick.
Coaching career
Forsythe became an assistant coach for the fledgling football team of Florida State College in 1903. Florida State College's head coach, W. W. Hughes, planned to use Forsythe as a fullback in a game against the University of Florida in Lake City, creating a controversy between the teams. For the 1904 season, the third and last for FSC's football team, Hughes transferred all coaching duties to Forsythe. The reason for this is unknown, but Hughes, who was also a Latin professor, may have taken on increased academic duties. Forsythe played on top of his coaching duties, and was probably paid. Under Forsythe, the FSC football team defeated the University of Florida at Lake City, and after defeating Stetson College, FSC was declared "champion of Florida" by The Florida Times-Union newspaper of Jacksonville. In 1905 the Florida Legislature passed the Buckman Act, which reorganized higher education in Florida. The University of Florida in Lake City was merged with three other institutions to form the new "University of the State of Florida", a school for white men. Florida State College became the Florida Female College, a school for white women, and a number of its former male students transferred to the new university. After the demise of the FSC football team, Forsythe coached the University School for Boys prep team in Stone Mountain, Georgia for a year. In May 1906, he was hired by the new University of the State of Florida to be its first director of athletics and to coach its first official football team in the coming fall season. Forsythe coached at Florida for three seasons from 1906 to 1908, and he compiled a 14–6–2 overall win-loss record. As measured by his winning percentage, he is currently the eighth winningest football coach in team history. In addition to his coaching duties for which he was paid $500, Forsythe also played on the team as a fullback and was purportedly paid an additional $500. In 1907, the Florida football team posted a 4–1–1 record, due in large part to the play of William Shands, who later was elected as a state senator and helped found the University of Florida College of Medicine.
