Boston Bruins captain Zdeno Chara was hospitalized overnight for dehydration.
The veteran defenceman's status for Game 2 of the playoff series against Montreal is unclear.
The Bruins said on their Twitter feed that Chara is being evaluated by the team's medical staff.
Chara felt ill after practising with the team Friday before being taken to the hospital.
He also missed the team's practice the next morning.
The Bruins trail the Canadiens 1-0 in the best-of-seven series.