Vasilevskiy, 21, would have been a restricted free agent after this season. He was 11-10-0 with a 2.76 goals-against average, .910 save percentage and one shutout last season, and 3-4 with a 2.76 GAA and .925 save percentage in eight games (six starts) during the 2016 Stanley Cup Playoffs. He took over as Lightning starter after Ben Bishop was injured in Game 1 of the Eastern Conference Final.
Selected with the 19th pick of the 2012 NHL Draft, Vasilevskiy is 18-15-1 with a 2.60 GAA and .913 save percentage in 40 NHL games.