Harold Wagstaff, also known by the nickname of "Waggy", was an English professional rugby league footballer who played in the 1900s, 1910s and 1920s. He played as a centre and was nicknamed the Prince of Centres. A captain of Great Britain, he also played representative rugby league for England, and Yorkshire. Wagstaff has been inducted into the Rugby Football League Hall of Fame, and the Huddersfield Giants Hall of Fame.

A rugby league team consists of 13 players on the field, with 4 substitutes on the bench. Each of the 13 players is assigned a position, normally with a standardised number, which reflects their role in attack and defence, although players can take up any position at any time.