In his NHL career, he played with the Edmonton Oilers, Ottawa Senators, Pittsburgh Penguins and Colorado Avalanche.

On January 4, 1991, Leroux's first regular season fight as a pro came in the American Hockey League (AHL) as a member of the Cape Breton Oilers where he took on Brent Grieve of the Capital District Islanders.

[citation needed] Prior to the start of the 1997–98 season, Leroux was traded to the Colorado Avalanche for a third-round pick in the 1998 NHL Entry Draft.

He later played for the Grand Rapids Griffins of the International Hockey League and the Springfield Falcons of the AHL.

Leroux played 57 games for the Wilkes-Barre/Scranton Penguins before being traded, along with Jan Hrdina to the Phoenix Coyotes for three prospects (forwards Ramzi Abid and Guillaume Lefebvre, and defenceman Dan Focht) on March 16, 2003.