John Dennis Boocker (22 November 1922[2] – 8 June 1987), also known by the nickname of "Dinny", was a Welsh professional rugby league footballer who played in the 1940s and 1950s.

[1][7] Dennis Boocker played at centre in Wakefield Trinity's 7–7 draw with Leeds in the 1947 Yorkshire Cup Final during the 1947–48 season at Fartown Ground, Huddersfield on Saturday 1 November 1947, played at centre in Wakefield Trinity's 8–7 victory over Leeds in the 1947 Yorkshire Cup Final replay during the 1947–48 season at Odsal Stadium, Bradford on Wednesday 5 November 1947, and played on the wing in the 17–3 victory over Keighley in the 1951 Yorkshire Cup Final during the 1951–52 season at Fartown Ground, Huddersfield on Saturday 27 October 1951.

A typical action picture of Denis Boocker taken during Trinity's game with Belle Vue Rangers in August 1935, when the Welsh-Australian scored four tries.

Extended the club try-scoring record just prior to his return "down under" in April 1954 – and he left in Wakefield many friends and exciting memories.

[7] Note: "Boocker" is mis-spelt as "Booker", i.e. without the 'c', on Page-78 of the book 'Wakefield Trinity RLFC - FIFTY GREAT GAMES'.