In June 1968, Plante was selected in an intraleague draft by the St. Louis Blues and signed for $35,000 for the 1968–69 season. In his first season with the Blues, Plante split the goaltending duties with Glenn Hall. He won the Vezina Trophy that season for the seventh time, surpassing Bill Durnan's record. While playing for the Blues in the 1969–70 playoffs against the Boston Bruins, a shot fired by Fred Stanfield and redirected by Phil Esposito hit Plante in the forehead, knocking him out and breaking his fibreglass mask. The first thing Plante said after he regained consciousness at the hospital was that the mask saved his life. That game proved to be his last for the Blues, and he was traded in the summer of 1970 to the Toronto Maple Leafs. He led the NHL with the lowest goals against average (GAA) during his first season with the Maple Leafs. At season's end, he was named to the NHL's second All-Star team, his seventh such honour. He continued to play for the Leafs until he was traded to the Boston Bruins late in the 1972–73 season, recording a shutout against the Black Hawks in his debut for the Bruins. He played eight regular season and two playoff games for the Bruins to finish that season, his last in the NHL.