John Prosser was born to Welsh parents at Stalybridge in Cheshire but the family moved to the north-east of England when John was a schoolboy and he later became captain of Stockton FC where he played as either a centre-half or wing-half. He played for them in two consecutive FA Amateur Cup Finals in 1907 and 1908, when they lost to Clapton and the Royal Engineers respectively. Although Prosser was never capped by England he played in the North versus South trial at Chelsea in 1908 and was chosen to be one of the non-travelling reserves for the Olympic Games later that year. A marine engine fitter, he joined the Heavy Brigade of the Royal Garrison Artillery as a gunner and was sadly killed in action at Arras, France in 1917. Prosser won Victory and British medals.