An alumnus of the Red Lake District Minor Hockey Association and the Peterborough Petes of the OHL, Mann was drafted 99th overall by the Boston Bruins in the 1995 NHL Entry Draft and appeared in 90 NHL games with the Bruins over four seasons. He was traded to the Dallas Stars in June 2001 for Richard Jackman but remained with their American Hockey League affiliate the Utah Grizzlies and never played for the Stars. He was then traded to the Nashville Predators in June 2002 for David Gosselin and a 5th round pick in the 2003 Draft. Mann went on to play just 4 games for the Predators.