He played cricket for Warwickshire and Marylebone Cricket Club, as a left-hand bat, and right-arm medium-fast bowler, playing representative rugby union (RU) for England (7s), and at club level for Coventry R.F.C., as a Hooker and representative rugby league (RL) for Great Britain and England, and at club level for Wigan, North Sydney Bears (two spells) and Manly-Warringah Sea Eagles as a round the corner style goal-kicking prop, hooker, second-row or loose forward.
Gray switched to rugby league with English club Wigan, and played at prop, scoring 4 conversions in their 19–9 victory over Salford in the 1973 Lancashire Cup Final during the 1973–74 season at Wilderspool Stadium, Warrington, on Saturday 13 October 1973.
[4] Gray won caps for England (RL) while at Wigan in 1975 against France, and Wales, in the 1975 Rugby League World Cup against France, and won caps for Great Britain (RL) while at Wigan in 1974 against France (sub) (2 matches), Australia (2 matches), Australia (sub), and New Zealand (3 matches).
Gray was one of the first players to introduce the now routine round-the-corner style of goal kicking to Australia, he won the 1976 Amco Cup 'superstar' prize for player of the competition, he was the 1982 Dally M Award-winning hooker, a series of broken forearms, and constant back pain ended his career in 1983.
John Gray was named on the bench in the North Sydney Bears Team of the Century.