An alumnus of the Halifax Mooseheads of the Quebec Major Junior Hockey League (QMJHL), Tanguay has his jersey retired. During his junior career, he was also a member of Canada's under-20 team at the 1998 World Junior Championships. Selected in the first round, 12th overall, by the Colorado Avalanche at the 1998 NHL Entry Draft, he began his NHL career with Colorado in 1999. Tanguay won the Stanley Cup with Colorado in 2001, scoring two goals in Game 7 against the New Jersey Devils.