Teammates immediately called for medical help after Bouwmeester slumped over with 7 minutes 50 seconds left in the first period. Emergency personnel rushed to the bench and soon took Bouwmeester away on a stretcher.

Bouwmeester appeared to be grabbing a drink of water when he began to fall slowly.

Ducks and Blues players gathered to see what was wrong before Bouwmeester was taken off the bench. The Blues followed Bouwmeester into the tunnel leading to their dressing room, and the Ducks went to their dressing room as well. The game was called off a few minutes later, tied at 1-1.

Bouwmeester’s father was at the game as part of the team’s annual Dads Trip. He went with his son to the hospital while teammates and their fathers remained at the arena awaiting updates. Players from both teams met for hugs and good wishes after changing out of their gear.

Bouwmeester is in his 17th N.H.L. season and has been known for his strong skating and conditioning. He helped the Blues win the Stanley Cup last season and won an Olympic gold medal with Canada in 2014.

Bouwmeester was playing in his 57th game this season, the 1,241st of his N.H.L. career. He skated 1:20 in his last shift before collapsing and logged 5:34 of ice time in the game.