Micky Kavanagh was born in 1927 in Dublin, and attended St Laurence O’Toole School, where Gaelic games were played but association football was not. He began his youthful football career with Stella Maris, Johnville and Bohemians, and as a 16-year-old, went to England for what proved a lengthy and ultimately unsuccessful trial with Hull City.
He returned to Dublin junior football, but another English trial in early 1948 led to a contract with Brighton & Hove Albion, He made his debut in November of that year, made 12 Football League Third Division South appearances in the 1948–49 season, and a further 14 in 1949–50.
While playing for the reserve team at the start of the following season, Micky suffered a knee ligament injury that forced him into retirement and was to cause him problems for the rest of his life. He then worked as a lathe operator for a local engineering firm, and in his spare time coached Sussex county League team Littlehampton Town for eight years.