Sharon Sinclair first joined the newly formed organization, Slo-Pitch National, in 1989, as umpire consultant and she faced what must have seemed a daunting task. She would be helping shape an infant slo-pitch tournament organizing body, and be working with a newly-created officiating committee in establishing a national rulebook, umpires manual plus developing clinic packages suitable for use all across the country in the training of new umpires all specific to the game of slo-pitch softball. At the same time the committee would be setting standards that would define SPNs level of excellence.
Sharon was obviously up to the task. Having played softball since childhood, she started officiating in 1965 after having finished umpires school with top marks. Her enthusiasm for the game and umpiring ability has taken her to the championship level provincially, nationally and internationally. She umpired her first Softball Canada Canadian fast-pitch championship in 1976 and served as deputy national UIC at their first Canadian slo-pitch championship in London, Ontario in 1979.
Sharon served for five years as provincial umpire-in-chief for Softball Ontario and while serving for five years as deputy national Umpire-in-chief for Softball Canada, she initiated an umpire clinic package which was used in Canada, the USA and Australia. She became Canada's first female level five (international) umpire in 1979 and represented Canada at such international events as the Pan American games, Mexico, 1982; and the International Cup, Los Angeles, 1984, where she did the plate in the final game between the USA and China.