Responding to questions about Horton’s fitness on the day after his team’s crushing 4-3 triple-overtime loss, coach Claude Julien’s update to the media was brief: “Day-to-day,” he said.

Horton, who is also the play-offs second leading scorer with seven goals and 18 points, left the ice during the first overtime period on Wednesday with what appeared to be a shoulder injury.

NHL teams are notoriously tight-lipped about injuries and are required to describe them only as being either upper or lower body.

If Horton’s injury is serious enough to keep him out of Saturday’s Game Two, it would be a huge blow for the Bruins, forcing Julien to retool what has been his top line.

David Krejci, Milan Lucic and Horton have been the play-offs hottest unit, combining for 21 goals and 57 points.

“He’s definitely a big part of our team but we’ll see,” said Bruins Patrice Bergeron. “Hopefully he’s fine.”

Julien said the Bruins are prepared to push ahead without Horton.

Tyler Sequin could be moved up to the top line but Julien said he would look at his options when Horton’s status is confirmed.

“We’ve worked everybody hard,” said Julien. “There’s nobody in that extra squad that isn’t ready to step in right now.”