|2018-2019||St. Louis Blues|
After 1,184 NHL regular-season games, Bouwmeester finally became a Stanley Cup champion on June 12, 2019, when he and the St. Louis Blues defeated the Boston Bruins 4-1 at TD Garden in Game 7 of the Cup Final. He had an assist on Ryan O'Reilly's first-period goal, led all players in ice time (28:34) in Game 7 and finished the playoffs with seven points, all assists, in 26 games.
But Bouwmeester's 2019-20 season came to a sudden end on Feb. 11, when he had a cardiac episode while on the bench during the first period of the game between the Blues and Anaheim Ducks at Honda Center. He was hospitalized for several days before being allowed to return home, but his season was over.