BOSTON — The Boston Bruins didn’t sign a bunch of pricey free agents over the summer after barely missing out on a Stanley Cup championship last season.

Instead, they handed out extensions.

After going to the last possible game of the season, losing to the St. Louis Blues in Game 7 of the Cup final, the Bruins are bringing back essentially the same roster for another try at their second NHL title of the decade. Coach Bruce Cassidy got a new deal, as did defensemen Charlie McAvoy and Brandon Carlo; captain Zdeno Chara received a one-year extension in March.

Cassidy took the Bruins to an Eastern Conference championship in just his second full season on the bench, thanks largely to a core of players from the team that won it all in 2011. And he’ll have the same nucleus this year: Chara on defense, Patrice Bergeron and Brad Marchand at forward, and Tuukka Rask in net.

Joining Bergeron and Marchand on the most potent first line in hockey is David Pastrnak, with David Krejci centering the second line. The 42-year-old Chara will team up with the 21-year-old McAvoy on defense, with Torey Krug (who’s 28) and Carlo (22) as the No. 2 pairing.

The mix of youth and experience is one of the team’s strengths.

“Look at guys around the league in their 30s, they’re really good players. Look at our guys in their 30s, we all had a really good season last year,” Krejci said. “We’re not a year older, we’re just a couple months older. So I feel like we’re in good shape and we’re ready to go.”

WHO’S HERE — F Brett Ritchie, F Par Lindholm.

WHO’S NOT — F Noel Acciari, F Marcus Johansson.

KEY PLAYERS — With his three-year deal, McAvoy is now the heir apparent to Chara as the team’s top defenseman for years to come. The line of Bergeron, Marchand and Pastrnak combined for 260 points in the regular season and 59 in the playoffs. Jake DeBrusk went from 16 goals in his rookie season to 27 last year. Rask played a six-year low of 46 games last year and is back in goal.

OUTLOOK — The Bruins are deep on defense, blending the aged Chara with players like McAvoy and Carlo. They have the most productive first line in hockey, but they are still looking for a second line right wing after finding no replacement for Johansson in the offseason. And then there are the injury issues that can beset an older team, chief among them Bergeron’s groin problem that has lingered into training camp.

PREDICTION — If Chara, Bergeron (34 years old) and Rask (32) can hold up, the Bruins can look forward to another long playoff run. They can’t count on other teams clearing out the Eastern Conference for them in the playoffs, though, so they’ll need to close the gap on Tampa Bay if they want to raise another banner in the new Boston Garden.