Toporowski was born in Paddockwood, Saskatchewan. After being drafted, Toporowski continued to play junior hockey for the Prince Albert Raiders of the Western Hockey League (WHL). In October 1994, the Kings traded him, Guy Leveque, Dixon Ward, and Kelly Fairchild to the Toronto Maple Leafs in exchange for Eric Lacroix, Chris Snell, and a fourth-round pick in the 1996 draft. The following two seasons, Toporowski played for the Maple Leafs' minor league affiliate, the St. John's Maple Leafs of the American Hockey League (AHL). In the 1996–97 season, Toronto called him up for three NHL games.