Sawchuk played his last great season as a Red Wing goalie in 1963-64. A pinched nerve put him in the hospital again during the playoffs—but he left, went to Olympia Stadium for the third game of the semi-finals, made twenty-six saves and shut out Chicago, then went back to the hospital. The Wings advanced to the finals, but lost to Toronto in seven games. Detroit hockey writers named Sawchuk the team's most valuable player of the season.
Still, Detroit let Sawchuk go in the waiver draft that year, and the Toronto Maple Leafs acquired him. The next year, he shared the Vezina Trophy with fellow Leaf goalie Johnny Bower. In 1966, he collapsed from back pain during a round of golf. Doctors discovered two herniated discs in his spine. He had surgery that fused two of his vertebrae together, and doctors warned he might not be able to play again. But that warning seemed to compel him to play even harder. His win-loss-tie record for the 1966-67 season was 15-5-4, and he achieved his 100th shutout that year.
In the 1967 semi-finals against Chicago, Sawchuk played the first four games, and won two and lost two. Exhausted, he insisted that Bower start the fifth game. But the coach put Sawchuk in to start the second period after Chicago scored two quick goals in the first period, shaking Bower up. Many hockey writers consider Sawchuk's performance that night the best game a hockey goalie ever played. A Bobby Hull slap shot hit Sawchuk in his tender shoulder and knocked him down, but he kept playing through the severe pain. Sawchuk made thirty-seven saves in two periods, robbing scoring champs like Hull and Stan Mikita. He didn't let in a goal, and the Leafs won 4-2. They went on to win the series, then defeated Montreal in six games to win the Stanley Cup, Sawchuk's fourth.