But it's not only that the Bruins have arguably the best line in the NHL. It's also their goaltending.
Coming off an impressive performance in the 2019 Stanley Cup Playoffs -- 2.02 goals-against average, .934 save percentage -- Tuukka Rask is having his best season since 2013-14, when he was voted the winner of the Vezina Trophy as the best goalie in the NHL. Among goalies to start at least 30 games this season, Rask leads the NHL in GAA (2.12), save percentage (.929), and is tied for second in shutouts (five), including one in the game before the pause to end the Philadelphia Flyers' nine-game winning streak. With backup Jaroslav Halak, who has a 2.39 GAA, a .919 save percentage and three shutouts in 31 games, the Bruins have perhaps the best goalie duo in the NHL.
The biggest criticism of the Bruins has been their depth beyond the top line, and they tried to address that before the NHL Trade Deadline by acquiring forwards Ondrej Kase and Nick Ritchie from the Anaheim Ducks. They also were counting on increased production from forward Charlie Coyle (16 goals, 21 assists).