Sealey began his career playing as an amateur for non-league side Warrington Town, before he moved to Liverpool in 1963 for a fee of £25. His solitary appearance came in Liverpool’s final game of the 1964-1965 season. In June 1966, Sealey, John Bennett and Alan Hignett all moved from Liverpool to Chester on free transfers.
Sealey made his debut in the second league game of the season, a 3–0 home defeat by Bradford Park Avenue and played in the following two games.
Sealey’s only other first-team games for Chester did not arrive until January 1968, when he made substitute appearances in a Welsh Cup tie against Bangor City and a Division Four match at Exeter City. This marked the end of his Chester playing career and he joinedo Wigan Athletic, where he made 22 league appearances.
He later moved on to Winsford United and, in November 1969, to Nantwich Town. John had to retire from football due to a serious knee injury in which he was never to recover.
John is now an avid Liverpool fan and holds a season ticket in the Main Stand of the ground.
John is known as “The Leader” by the people who venture to the game with him.