As the Boston Bruins and St. Louis Blues prep for game three of the Stanley Cup Final Saturday night, we now know that B's defenseman Matt Grzelcyk is in concussion protocol and the Blues player who caused the injury, Oskar Sundqvist, is suspended for one game.

The play happened in the first period of game two and left the Bruins shorthanded with just five defenseman.

The league held a hearing on the play in question and ruled it was an illegal boarding play.

The NHL Department of Player Safety issued this report...

Grzelcyk did not fly to St. Louis with the team for the next game. He has been a steady blueliner for the B's, scoring three goals and assisting on four goals in the playoffs.

Sundqvist is a fourth line center for the Blues. He has scored four goals and had five assists in the playoffs.

NOTE: Look for John Moore to replace Grzelcyk as one of the six defensemen for the Bruins...Another injured defenseman, Kevan Miller, is not ready for play. He has been on the injured list for several weeks with a knee issue.