Joe Mercer was probably the most influential Arsenal player in the period immediately following the Second World War.
Originally an attacking midfielder (then known as a wing half) Joe was signed by manager Tom Whittaker from Everton at the age of 32 in 1946.
Uniquely he was allowed to live and train on Merseyside and just join his new team mates on matchdays.
He was appointed captain and asked to play a more defensive role and add authority to the defence.
He did this so effectively that he led the Gunners to two League titles in 1948 and 1953 and two Cup Finals in 1950 and 1952. (With thanks to Doug Parry)