With the renamed, Mississauga Steelheads, during the 2012–13 season Martin was an invited participant at the 2013 CHL Top Prospects Game where he led Team Orr to a rare shutout win, and he helped Canada men's national under-18 ice hockey team win gold at the 2013 IIHF World U18 Championships. Leading up to the 2013 NHL Entry Draft. Martin was rated as a top prospect. He was the fifth goalie selected in the draft, when he was selected 63rd overall by the Colorado Avalanche.