Before playing in the NHL, Stajan played 3 seasons with the Belleville Bulls of the Ontario Hockey League (OHL). He was drafted with the 57th overall pick by the Toronto Maple Leafs in the 2002 NHL Entry Draft. On January 31, 2010, the Maple Leafs traded Stajan along with Niklas Hagman, Ian White and Jamal Mayers in exchange for Dion Phaneuf, Fredrik Sjöström and Keith Aulie.