As some of you have already mentioned, IF your going to discuss the best goalie(s) who have played for the Maple Leafs since 1970, perhaps we should go right back to the 1970-71 season. According to records.nhl.com, Jacques Plante of the Toronto Maple Leafs has the highest save percentage in a single season (1970-71) for any NHL goaltender from 1955 to present.
His save percentage was .944. His goals-against average was 1.89
Jacques Plante, Toronto Maple Leafs 1970-71:
Games Played: 40
Goals Against: 73
Saves: 1,224
Shots against: 1,297
Save percentage: .944
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Goals Against average: 1.89