The Montreal Canadiens - in the final year the National Hockey League team had the privilege to do so - invoked its right to select two French Canadian players first and second overall to pick Tardif in the first round, second overall, of the 1969 NHL Amateur Draft.

Tardif spent most of the 1969–70 NHL season with the American Hockey League (AHL) Montreal Voyageurs, one of the leading scorers on a team studded with future NHL stars, including Jude Drouin, Guy Charron, Guy Lapointe and Pete Mahovlich.

He was the Sharks' leading scorer that season, and was named to play for Team Canada in the 1974 Summit Series the following fall.

Tardif's playoffs were cut short after he incurred serious head injuries in an attack (on April 11, 1976) by Calgary Cowboys enforcer Rick Jodzio, leading to one of the first cases where a hockey player was charged in a court of law for assault.

[1][2] The next season Tardif was named the captain of the Nordiques, and recovered to post another 100-point campaign while leading the team to their only WHA championship, and followed that up in 1977–78 with a 154-point campaign - setting a professional hockey record eventually broken by Wayne Gretzky (who would score 164 points in the 1980-81 NHL season)- for which he received his second league MVP award.