One of three brothers who all played soccer professionally, Cock also became a star of stage and screen.  Having played for minor clubs, Cock signed for Brentford (1914) scoring two goals in his first, of only three matches, before being signed for Huddersfield Town as a professional.   His career was put on hold by the advent of the First World War during which he was awarded the Military Medal (MM). 

Having rejoined Huddersfield Town in 1918, he signed for Chelsea for the then record fee of £2,650 and he, again, scored two goals on his debut against Bradford City.  In the same year he won his full cap for England when, playing against Wales, he again scored.  He was also the main reason for Chelsea finishing 3rd in the First Division, having scored 23 goals in 30 matches and for Chelsea reaching the semi-finals of the FA Cup.  In the second of his only two games for England he scored against Ireland just 30 seconds into the match.  Cock transferred to Everton FC before joining Plymouth Argyle in 1925 and then Millwall where he remained until retiring but where he returned as manager in 1944.

He is one of the few people to have played himself on film when he appeared in ‘The Winning Goal’ (1920) and in ‘The Great Game’ (1930).