The Bruins are in the Cup Final for the third time this decade; they won the Stanley Cup in 2011 and lost in the championship round in six games against the Chicago Blackhawks in 2013.
It has been 49 years since the Blues have gotten this far and they're still seeking their first Cup Final win. They reached the Stanley Cup Final three consecutive years from 1968-70, but were swept each time, including by the Bruins in 1970.
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Since the Cup Final went to a best-of-7 format in 1939, the team that has won Game 1 has won the Stanley Cup 77.2 percent of the time (61 of 79). However, the Washington Capitals rallied to win four games in a row after losing Game 1 against the Vegas Golden Knights last year.
Here are 5 keys to Game 1:
1. Stripping away the rust
The Bruins have had 10 days off between games. They have tried to stay sharp by holding hard, fast-paced and quick practices. They also played an intrasquad scrimmage in a sold-out TD Garden on Thursday. But they are still curious about how the long layoff will impact them.
"Until we play, right, it's going to be hard," Bruins coach Bruce Cassidy said. "I think they've handled it well. We've mixed in rest versus work. Yesterday our practice was scruffy, I'm not going to lie to you. I thought the day before was excellent. As a coach, which one do you take? I trust the leadership group that they'll have our guys ready."
The Blues haven't played since last Tuesday, when they defeated the San Jose Sharks 5-1 in Game 6 of the Western Conference Final.
Video: Key points ahead of Game 1 of the Stanley Cup Final
2. Goalie matchup
All eyes will be on Blues rookie goalie Jordan Binnington to see how the 25-year-old handles his first steps onto the biggest stage in the NHL.
Binnington comes into the series with a three-game winning streak featuring a 0.67 goals-against average and .974 save percentage (two goals on 77 shots). He needs one win to become the third rookie goalie in NHL history to win in each of his team's first 13 wins in the same postseason.
The record is 15, co-held by Patrick Roy (1986, Montreal Canadiens) and Ron Hextall (1987, Philadelphia Flyers).
In the other net will be Bruins goalie Tuukka Rask, who has already been on this stage twice before. He didn't play in 2011 when Boston won the Stanley Cup but was their No. 1 in 2013 when it lost against the Blackhawks.
Rask has won seven in a row with a .961 save percentage and 1.29 GAA.
3. Something special
What makes the special teams in this series so compelling is the way the Bruins have dominated on both the power play and penalty kill in the playoffs, especially during their seven-game winning streak, and how it has helped carry them into the Cup Final.
Boston is first on the power play (34.0 percent) and fourth on the PK (86.3 percent) during the playoffs. During their seven-game winning streak, they are 37.5 percent on the power play (9-for-24), including 46.7 percent (7-for-15) in the conference final, and 95.8 percent on the PK (23-for-24).
The Blues have not fared as well in the special teams game overall (19.4 percent PP, 78.0 percent PK), but they are 5-for-15 (33.3 percent) on the power play in their past four games and 11-for-13 (84.6 percent) on the PK in their past six games.
4. Figuring out the forecheck
The Blues and Bruins each build their offense off the forecheck.
They're aggressive on it. They grind and force the opposition to take the puck wide. They limit rush attempts and make east-west passes difficult to connect. If the opposition gets through the neutral zone, each team stands up well at the blue line, making it hard to get a clean zone entry.
Whoever forechecks better in Game 1 will have the puck more and therefore gain the upper hand.
5. Bergeron and O'Reilly
St. Louis center Ryan O'Reilly and Boston center Patrice Bergeron each is a finalist this season for the Selke Trophy, awarded to the best defensive forward in the NHL. It'll be interesting to see how often they match up against one another in Game 1.
Cassidy said his goal is to get Bergeron and his linemates, Brad Marchand and David Pastrnak, on the ice against the Blues' top line of Brayden Schenn, Vladimir Tarasenko and Jaden Schwartz.
Tarasenko has points in six straight games (three goals, five assists). Schwartz has 12 goals in the playoffs.
That likely leaves the fourth line of Sean Kuraly, Noel Acciari and Joakim Nordstrom to match up against O'Reilly's line, which also features Sammy Blais and David Perron. Cassidy, though, left open the possibility he could switch Bergeron's line around if necessary.
If St. Louis coach Craig Berube can swing it, he might try to get O'Reilly's line on the ice against Bergeron's line to force it into defensive situations. It's part of the game within the game that could determine the outcome of Game 1.
Blues projected lineup
Jaden Schwartz -- Brayden Schenn -- Vladimir Tarasenko
Sammy Blais -- Ryan O'Reilly -- David Perron
Pat Maroon -- Tyler Bozak -- Robert Thomas
Ivan Barbashev -- Oskar Sundqvist -- Alexander Steen
Joel Edmundson -- Alex Pietrangelo
Jay Bouwmeester -- Colton Parayko
Carl Gunnarsson -- Robert Bortuzzo
Scratched: Robby Fabbri, Michael Del Zotto, Zach Sanford, Mackenzie MacEachern, Chris Thorburn, Ville Husso
Injured: Vince Dunn (upper body)
Bruins projected lineup
Brad Marchand -- Patrice Bergeron -- David Pastrnak
Jake DeBrusk -- David Krejci -- David Backes
Marcus Johansson -- Charlie Coyle -- Danton Heinen
Joakim Nordstrom -- Sean Kuraly -- Noel Acciari
Zdeno Chara -- Charlie McAvoy
Torey Krug -- Brandon Carlo
Matt Grzelcyk -- Connor Clifton
Scratched: John Moore, Steven Kampfer, Karson Kuhlman
Injured: Chris Wagner (upper body), Kevan Miller (lower body)
Thomas did not participate in the Blues' morning skate, but he will be in the lineup, Berube said. … Marchand, who didn't practice Sunday, will play, Cassidy said. … Chara, who sat out Game 4 against Carolina on May 16 with an undisclosed injury, will play. … Dunn will miss his fourth straight game.
Listen: Stanley Cup Final preview from NHL Fantasy on Ice podcast