The defenseman will replace Robert Bortuzzo, who will be a healthy scratch. Forward Robert Thomas also will not play because of what Craig Berube called a coach's decision.
Thomas will sit to make room for the return of Ivan Barbashev, who was suspended by the NHL Department of Player Safety for Game 6, which the Blues lost 5-1 on Sunday, for an illegal check to the head of Bruins forward Marcus Johansson in Game 5.
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With the Stanley Cup going to the winner Wednesday, Edmundson is thrilled to get a chance to play after being a healthy scratch for two straight games.
"This will be a [heck] of a game tonight," Edmundson said. "We're excited. We're a confident group right now, so we're just looking to get things going."
Berube said the decision play Edmundson, a lefthanded shot, over Bortuzzo, a righty, was based on Colton Parayko and Alex Pietrangelo playing heavy minutes on the right side. Parayko is averaging a Cup Final-high 26:51 in ice time per game and Pietrangelo is second in the series averaging 26:21.
"They're eating so many minutes up, there's not a lot of minutes over there," Berube said. "So we decided to go with the four lefties."
Edmundson has seven points (one goal, six assists) in 21 Stanley Cup Playoff games.
"He can bring a lot," Berube said. "He's got some real good upside. He shoots the puck well. A big guy, big body (6-foot-4, 215 pounds), physical player. But he does do some things well in the offensive zone. I like his shot."
Thomas, who did not participate in the Blues optional morning skate or practice Tuesday, missed four straight games with an unspecified injury before returning to the lineup in Game 6. He has six points (one goal, five assists) in 21 playoff games. Barbashev, who has six points (three goals, three assists) in 24 playoff games, will return to his usual spot at left wing on the fourth line with Oskar Sundqvist and Alexander Steen.
