The 23-year-old has signed a one-year deal with the option of further twelve months at Bootham Crescent after impressing manager Jackie McNamara during a two-week trial.
Clarke began his senior career with Evo-Stik League Southern Division One South & West side Wimborne Town after being spotted playing for Bournemouth University where he had begun studying for a degree in sports psychology and coaching.
The 6`1” Liverpudlian then moved to Sydenhams Football League (Wessex) outfit Blackfield & Langley before returning to former club Wimborne in early 2015.
After impressing at The Cuthbury, Southern Premier Division outfit Dorchester Town swooped for his services in late 2015 and Clarke spent the next six months with the Avenue Stadium.