Matthew Stajan was born December 19, 1983 in Mississauga, Ontario. The second round, 57th overall selection of the Toronto Maple Leafs in the 2002 NHL Entry Draft, Stajan is a graduate of the OHL's Belleville Bulls.
In three seasons with the Bulls, Stajan registered 206 points (76-130-206) in 182 games. A member of Canada's silver medal World Junior Team in 2003, Stajan saw his first professional action in the latter stages of the 2002-03 AHL and NHL seasons.
After getting a taste of the NHL in 2002-03, Stajan made a strong for a roster spot in 2003-04. With a solid training camp and pre-season, Stajan earned a regular roster spot with the Leafs for the 2003-04 season. In 69 games, Stajan registered 27 points (14-13-27) and was named to the 2004 NHL All-Star Young Guns Game. In 2005-06 Stajan became a regular in Toronto, competing in 80 games, he once again tallied 27 points.
Over the next pair of seasons Stajan would become one of the more responsible and consistent Maple Leafs. While the club struggled both on the ice, Stajan twice broke the 30-point mark and suited up for his 300th NHL game on March 4, 2008.
On January 31, 2010, Stajan was shipped to the Calgary Flames as part of a seven player trade that saw the Maple Leafs acquire Dion Phaneuf.