Ernie Peters journey in softball began with his playing minor softball in Steinbach. Over the next few years he honed his pitching skills and led the Southeast Mennonite Church team to a league championship. Advancing through the Cloverleaf Fastball League and the Winnipeg Industrial League, Peters' senior softball career began in 1966 with the Molson Canadians. They won both the Winnipeg and Manitoba Senior Championships that year. Peters moved to the Black Knights in 1967, a team that captured the Industrial League and Manitoba Intermediate Championship in 1967 and 1968. Moving back to senior competition in 1969, the Black Knights dethroned Molsons in an eight game series to capture the Manitoba Senior League Championship. In 1969, Peters was also recruited to pitch in the Canada Summer Games in Halifax. As a member of the Black Knights, Peters represented Manitoba at the Canadian Senior Championships in 1970 and 1971.