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In honour of Börje Salming's exceptional contributions to the Toronto Maple Leafs organization, jersey number 21 was retired on December 17, 2022. Salming, a Swedish defenceman, played for the Maple Leafs from 1973 to 1989 and became a beloved figure known for his toughness and offensive prowess. His retirement ceremony was a significant moment of recognition for his impact on the team and the sport of hockey.