Before playing in the NHL, Polák played parts of 1 season with the Kootenay Ice of the Western Hockey League (WHL) and half of 1 season with HC Vítkovice Steel of the Czech Extraliga. Polák played for Czech Republic during the 2004 IIHF World U18 Championships and the 2005 World Junior Ice Hockey Championships. He won a bronze medal at both tournaments. He was drafted 180th overall by the St. Louis Blues in the 2004 NHL Entry Draft.