Drafted 58th overall in the 2012 draft by Phoenix, the Leduc, Alberta native had a breakout year last season. Notching 40 goals and 24 assists with WHL's Vancouver Giants. Its assumed that Martinook will skip his final year with the Giants to play for the Coyotes' AHL affiliate, the Portland Pirates as he told The Province newspaper,
"They told me I’m not coming back here. I’m going to miss Vancouver, but they said they want me in Portland [AHL] or Phoenix, depending on what happens."
In 144 games with the Vancouver Giants, Martinook has 51 goals and 41 assists, adding 10 more points during the Giants' playoff runs, back to back.