Sergeant played for St Sidwell's United in local football before the club became Exeter City in 1904.

Although records do not survive for every game it is apparent that he played several times during 1903/04, the final season of St Sidwell's United's before it became Exeter City. 

The 1901 census includes William Sargeant (alternative spelling), a twenty-year-old printer living at Cambridge Terrace, Well Street very close to St James' Park.