This first part is going to be painful so let's get it over with. The Bruins are good. Real good. They've become a solid 5 on 5 squad that's supported by good goaltending, good enough to be one of the few Eastern Conference teams that could legitimately consider themselves Cup contenders. The bastards.
The Bruins' roster stability and annoying tendency to avoid major injuries has resulted in lines with well established track records whose effectiveness is easy to measure. I avoid the stupid convention of putting Krejci's line on top, Patrice Bergeron's group is the most important especially with Tyler Seguin's break out campaign. Big Nose-Nords Fan-Leaf's Pick tend to take on the shutdown role for the Bruins but not to the extent they did when Recchi was in Seguin's place. Top six opposition and even zone starts was the trend, this year Julian seems to favour giving them an offensive role. They were dominant last season, ~+21 shot attempts per 60 minutes last year which helped lead Bergeron to a +32 goal differential on 5 on 5 play. About half of the Bruins' +67 goal differential is due to what happened with this unit on the ice last season. Simply put, stopping an ursine rampage starts by putting these three into their cage at even strength. Their puck possession numbers this season resemble the last so don't count on Bergeron's group having lost any of their potency. Marchand may not play this game, if so he'll be replaced by .86 PPG AHL call up Ryan Spooner.
The Ugly Thugs and the Czech line is typically ranked first, but is not as dangerous as the other unit. The basis of this line's effectiveness is a skilled play-maker with a decent two-way game playing with two big guys that can shoot for high percentages. Lucic isn't a real 30 goal man without extra help from empty netters but both he and Horton have no trouble clearing 20 in a regular year. A dangerous line, but I've never been that frightened of them as a Habs fan. To many times seeing Tomas Plekanec show how to make fools of them by closely marking the only guy with puck skills in Krejci and leaving the big guys high and dry.
The Bruins' third unit is usually a fairly solid depth scoring unit, taking advantage of matchups freed up by their threatening top six. It looks weaker than usual this time around, with nepotism hire Chris Bourque whose a career AHLer brought in to help the Bruins wretched powerplay. His presence appears to have dragged a solid pair of forwards into negative possession territory due to a massive (about 25%) drop in shot attempts for. But I do believe the SM-Liiga has well shown that Pevelry is an inferior player to Habs current 4th line center Lars Eller, where the Dane was the dominating 1st line center and the Bruin was his caddy.
The Bruins 4th line tend to get smacked around in hockey terms, normally well below water on puck possession but their job is to hit people and create shocking conflicts of interest in the NHL head office. But Paille and Thornton are injured and not in the lineup. So the Bruins are playing two guys they aren't willing to give even 5 minutes of ice time to. Expect the 4th line to be a complete non-factor.
Game Time Edit:
Marchand is out but Spooner is expected to center the 4th line while Campbell moves up to Bergeron's wing. Marchand is the weakest of that trio but expect a sharp drop in efficiency from losing him for a 4th liner of little distinction.
Chara stands out from the pack as the 2nd greatest ES defenseman of the past few years behind only the legendary Lidstrom. In the past 5 years his goals ratio is 58.8% (3rd), his corsi ratio 54.6% (8th) all while taking the bulk of his team's shutdown assignments. The combination of him and Patrice Bergeron have been the beating heart of the Bruins, combining to have their team a whopping 61.9% of the goals and 56.4% of the shot attempts when they are both on the ice. The axis of one off the league's best two-way center/defenseman combinations is the secret to the Bruins recent run of success. Zack Boychuk is Chara's largely unremarkable partner who has a job that's just as cushy as H.Sedin's right wing.
The downfall of the Bruins tends to be that the defensemen after Chara tend to be a pack of smucks that keep things about even despite all the hard work done for them by the superstar, relying on the Bruins goaltending to keep their asses out of the fire. Seidenberg is the best of that lot, typically able to anchor a respectable if not brilliant 2nd pairing. He's joined by young Hamilton, the latest fruits of Brian Burke's laughable ineptitude. Hamilton is getting sheltered so far but he's had a disgusting tendency to control puck possession so far, having the Bruins' best corsiRel.
McQuaid and Ference aren't very good hockey players tending to be in the pits for their team on possession despite butter soft minutes, and the later shows a shocking lack of social graces in playoff games at the Bell Centre, but the Bruins don't ask that much out of them but hitting things and they can deliver on that.
The key to beating this group is simply being deep enough to put up a strong attack when Chara isn't on the ice. The Bruins recent history of winning reflects the difficulty of assembling that much talent on one team.
The Bruins turn from apex predators into prey on the powerplay. They have many of the classical powerplay elements on their team, a giant point shot in Chara and a bunch of characters that can crash the net. But they are absent anyone with real offensive creativity. Their on ice corsi tops out beneath 70 when the league mean tends to be around 80, combined with inept shooting so far and they sit with a microscopic 10.0% conversion rate on the PP. Expect that rate to go up but they haven't been above average with the man advantage since Marc Savard got his head scrambled.
Bruins aren't completely inept at special teams, both their PK units are well above average, Chara-Boychuck/Kelly-Pevelry in particular have been dominant early. Just like they have difficulty breaking 70 corsi per 60 on the PP, the Bruins PKers are all ~70 or under on the penalty kill, which has helped them earn a 94.1% effectiveness rating so far. I doubt they are quite this good on the kill, but they were fairly strong last year as well. They could be a hard nut to crack with the man-advantage.
Taking on the Bruins means loading for bear. Good thing the Habs are healthy and brought a tougher mammal with them:
If the Habs play to potential they are a rare team that can match the Bruins depth up and down the lineup. ~60% corsi close Plekanec and his minions can stand against Bergeron, while Pacioretty, Desharnais and Cole can counter Krejci. Then it's a battle of depth on depth, where Montreal should have a significant advantage this time around. Alex Galchenyuk's tertiary scoring unit could be a major advantage for the Habs due to Boston's diminished bottom six. On defense one of Subban and Markov can hold ground on Chara while the other is out against the lesser lights. Ultimately the Habs most frequent path to victory is to hold the game even at even strength and then use their special teams superiority to tip the balance.
Boston was a 52.60% Fenwick close squad on 5 on 5 (6th) last season with a stratospheric save percentage, which lead to massive dominance on even strength. This season they continue to be strong on 5 on 5 puck possession (54.50%/5th) although their goaltending have been a more human .914 5 on 5. They are one of the few teams in the East I think are undoubtedly good overall and present both a major challenge and a good measuring stick game to see if Montreal's early dominance has been an artifact of a soft schedule. Traditionally the Habs have beaten the Bruins on special teams while losing 5 on 5, it would be interesting to see if this healthy Canadiens squad can beat the Bruins at their own game.