Harry Riley had appeared for a number of clubs, most notably Lincoln City, when he joined Exeter City from Northampton in 1938. With the war interrupting his career, he played semi-professionally in the Lincoln area after 1946.

Harry started with Altrincham, and later played for Hurst, before joining Birmingham City in 1928 for whom he only played one league match. Moving to Ashton National, he was given another Football League opportunity when signing for Accrington Stanley in 1930 where he scored 18 goals in 32 league outings ahead of switching to Lincoln City for whom he was a member of the team that won the 1931/32 Third Division North championship. A cricketer too, he played for Lincolnshire during his time at Sincil Bank and subsequent years in the area. 

Harry's next club was Notts County followed by Cardiff City (between 1934 and 1936) and two seasons at Northampton Town. With the possibility of a job combined with footbal he was all set to return to the Lincoln area upon leaving the Cobblers but, when this fell through,  he received an alternative offer from Exeter City. Making his Grecians debut in a 4-0 defeat at Watford in November of 1938 Harry made 26 league appearances in his first campaign with City and, after playing against Plymouth Argyle in a Jubilee Fund game in August 1939, featured in two league games in 1939/40 (scoring twice) before war intervened and the season was abandoned. He then returned to the Lincoln area where he played in post-war football for Ruston Bucyrus before managing Lincoln City’s reserve team. 

Harry died in Lincoln on 8 April 1982 at the age of 72.