Bruins aim to evolve under Cassidy

After the Boston Bruins reached the Stanley Cup Playoffs for the first time in three seasons before losing to the Ottawa Senators in the Eastern Conference First Round, they decided they didn't need any outside help to achieve their goal of going further.
The Bruins didn't make any major free agent signings or trades, a vote of confidence to several veterans who need to have a turnaround season and to prospects who have a chance to move up the depth chart in a hurry.

With Bruce Cassidy, who took over as coach for Claude Julien on Feb. 7, the Bruins will look to build off what they accomplished last season.
"Last year, you're thrown into it, we knew what was at stake, the urgency level, so that was built in right away, that was an advantage," Cassidy said. "This year, we want to make sure we get off to a good start and have the urgency from opening night on. I think guys enjoyed being back in the playoffs, and that's not easy. It's not an automatic. You've got to earn your way through there."
Here is a look at the five keys for the Bruins, the inside scoop on their roster questions and projected lines for the 2017-18 season:

5 KEYS

1. Find a third-line center
The Bruins boast a terrific one-two punch of Patrice Bergeron and David Krejci at center. But Ryan Spooner's struggle to establish himself as the No. 3 weakened their lineup the past few seasons.
Spooner will be challenged by rookie Jakob Forsbacka Karlsson and other candidates, including David Backes, Riley Nash and Tim Schaller. Ideally, Spooner, who signed a one-year, $2.825 million contract as a restricted free agent July 26, would use his high-end speed and skill to solidify the position.
"They could've signed me to two or three years, they didn't, it's a one-year deal," Spooner said. "So I have to go out there and show them I'm here to play. That's the plan."

2. Thrive with younger defensemen
The Bruins worked Brandon Carlo, 20, into their defense last season as a rookie for all 82 games and then added Charlie McAvoy, 19, to the mix in the playoffs after he played four games in the American Hockey League following his sophomore season at Boston University. Even if just Carlo and McAvoy are in the lineup, the Bruins are going to have to succeed with inexperience from one-third of their defense.
"I think just realizing there's going to be bumps along the way," defenseman Torey Krug said. "If we can manage those and make sure those time periods are shorter than the successful lengths of time, then we'll be all right."
3. Rest for Rask
Goaltender Tuukka Rask played 65 games last season, 64 in 2015-16 and 70 in 2014-15. His numbers have been strong, but he showed down the stretch last season that he's at his best when he's rested. If one of Anton Khudobin, Malcolm Subban or Zane McIntyre can be a valuable backup, the Bruins will be better.
"I think that the biggest thing is we're looking to make the playoffs and we're looking to make a run in the playoffs, so you want to be fresh come June," Rask said.
4. Fill the wings
Cassidy likes to pair up forwards, so Bergeron and Brad Marchand will stick together, as will Krejci and David Pastrnak. The Bruins have to find a right wing for the Bergeron-Marchand line and a left wing for the Krejci-Pastrnak line. Backes, Schaller and Frank Vatrano could be in the mix, as could prospects Anders Bjork, Jake DeBrusk and Danton Heinen.

5. Keep up the pace
When Cassidy took over, he preached speed. He wants to play faster this season after the Bruins have a whole training camp to learn his system. The up-tempo game paid off with the Bruins averaging 3.37 goals per game under Cassidy after averaging 2.56 prior. With some older players and some inexperienced young ones in the lineup, it will be interesting to see if the Bruins can play Cassidy's style.

ROSTER RUNDOWN

Biggest lock
Bergeron's offensive numbers may have dipped (53 points last season after 68 in 2015-16), but he won his fourth Selke Trophy and led the League with 1,089 faceoff wins. Offseason surgery to repair a sports hernia that nagged him all season should help him improve even at 32 years old. "I'm trying to get back to my game, playing both ways, and you always want to push your limits, be better offensively but also defensively and in every aspect of the game," Bergeron said.

Biggest battle
One of the most coveted lineup spots is at right wing next to Bergeron and left wing Marchand, whose 39 goals led the Bruins last season. Pastrnak, who filled that spot most of last season, likely will play on Krejci's line, meaning Backes and a group of younger players, including Vatrano and Bjork, will compete for the position.
Most intriguing addition
The Bruins got a taste of what McAvoy, the No. 14 pick in the 2016 NHL Draft, could do in the League during his six-game playoff stint. McAvoy had three points and averaged 26:11 of ice time playing in all situations. Having McAvoy for a full season could help the Bruins challenge for first place in the Atlantic Division.
Biggest potential surprise
After signing a five-year, $19 million contract with the Bruins on July 1, 2015, as an unrestricted free agent, left wing Matt Beleskey had 37 points (15 goals, 22 assists) in 2015-16. Last season, an injury limited him to 49 games, and he had eight points (three goals, five assists). The Bruins are hoping he can find his form and solidify their top nine. "Just got to have some confidence, stick with my game," Beleskey said. "I don't think you lose your hockey playing ability in one year."

PROJECTED LINEUP

Brad Marchand -- Patrice Bergeron -- David Backes
Frank Vatrano -- David Krejci -- David Pastrnak
Matt Beleskey -- Ryan Spooner -- Riley Nash
Tim Schaller -- Sean Kuraly -- Noel Acciari
Zdeno Chara -- Brandon Carlo
Torey Krug -- Adam McQuaid
Kevan Miller -- Charlie McAvoy
Tuukka Rask
Anton Khudobin