On March 2, 2020, Stamkos had surgery to repair a core muscle. Stamkos recovery was projected at 6–8 weeks from the procedure, which caused him to miss the remainder of the regular season. On September 23, 2020, Stamkos returned to the Lightning lineup in the third game of the Stanley Cup Finals. Stamkos scored his first goal of the post season on his first shot of the game. Stamkos' goal was the second time in NHL history that a player skating in their first game of the playoffs in the Stanley Cup Final scored a goal. The last time the feat occurred was over 80 years ago by Billy Taylor Sr. in 1940. Stamkos logged just 2:47 of ice time during the game, but he managed to score a goal on his only shot. He played only one game of the Stanley Cup Finals and during the 2020 Stanley Cup playoffs. The Lightning would go on to win the Stanley Cup, marking Stamkos' first championship.