Malarchuk, who was born in Grand Prairie, Alberta, played junior hockey in the Western Hockey League. He went on to play professionally in the NHL for the Quebec Nordiques, the Washington Capitals, and the Buffalo Sabres, and in the IHL for the Las Vegas Thunder.
After leaving the NHL as a player, he served as head coach of the IHL Las Vegas Thunder and the Idaho Steelheads. He was then a goaltending coach for the NHL Florida Panthers and the Columbus Blue Jackets. He became the goaltending consultant for the Atlanta Thrashers in 2010, going from there to the Calgary Flames, and retiring from the team in 2014.