Career
In September 1963, Mestinsek was invited to join the Detroit Red Wings training camp, turning professional to play with the Red Wings minor league affiliate in the Central Professional Hockey League. Mestinsek started the 1966-1967 season playing with the New York Rangers" CPHL affiliate, the Omaha Knights. In 1967, the Saint Louis Blues selected him from the New York Rangers in the National Hockey League Expansion Draft.
Following a car accident in August 1967 in which he almost lost his arm, the player who was once described by Punch Imlach as “the best National League material in Western Canada” saw only limited action over the next two seasons spent mostly with the Kansas City Blues of the CPHL. His playing career was cut short by a car accident, but he remained close to the game, and was later an off-ice official at Vancouver Canucks games.