BOSTON — The Bruins’ second full week of training camp will see veterans such as Patrice Bergeron, David Krejci, Zdeno Chara, Brad Marchand, Tuukka Rask and Torey Krug filter into the lineup for preseason games — some perhaps as early as Monday night, when the Flyers visit TD Garden.

Those long-timers, who have all played in two or three Stanley Cup finals since 2011, aren’t ready yet for the Oct. 3 regular-season opener at Dallas. They may not even be as [...]

BOSTON — The Bruins’ second full week of training camp will see veterans such as Patrice Bergeron, David Krejci, Zdeno Chara, Brad Marchand, Tuukka Rask and Torey Krug filter into the lineup for preseason games — some perhaps as early as Monday night, when the Flyers visit TD Garden.

Those long-timers, who have all played in two or three Stanley Cup finals since 2011, aren’t ready yet for the Oct. 3 regular-season opener at Dallas. They may not even be as ready to play preseason hockey as they’d normally be at this time of year, but they’re not too concerned. Playing until June 12 last season chopped a significant chunk from their preparation time for the coming season, but they’ve learned how to adjust.

First-timers? Not so much. Younger players who had barely played hockey into May before last year are in unfamiliar territory.

“You feel like you’re just starting to get your energy back” from the previous season, said winger Jake DeBrusk, “and that’s when you get thrown right back into the fire. We’re already in training camp, more than a week in. It happens fast.”

DeBrusk is among a core of young B’s who have grown into full-time NHLers over the last few seasons, but most of them still have room for physical growth. This summer, however, they didn’t have as much time as usual to work on that.

“Usually, you get two or three, sometimes even four months, to get into your weight-lifting regimen, get on your eight-week, 12-week program,” said defenseman Charlie McAvoy, who had previously played as late as May 20 in 2018, when he joined Team USA for the IIHF World Championships. “Obviously, with the shrunken offseason, I think for all of us, it was more about rest time. You do get into your strength training, but now your eight- or 12-week block is a five-week block.”

Head coach Bruce Cassidy — who, like his youngest players, is a stranger to a short offseason — expects the players’ abbreviated training periods to show up at some point. He has been cautious and considerate during training camp with veterans, especially Bergeron and Chara, who were injured after last year’s run to Game 7 of the Cup final.

Younger full-timers — DeBrusk, McAvoy, Brandon Carlo, Danton Heinen, Sean Kuraly — are on a somewhat shorter leash. Cassidy thinks they should be able to give a little more at the start of the year, as veterans round into form.

DeBrusk gets that.

“That is a goal, or a focus,” he said. “As younger guys, we should have the energy and the speed and all those things people talk about.”

Cassidy won’t know if he’s right until he sees it.

“It is a concern that these guys have lost a bit of training time,” he said. “Will they hit a wall sooner, because they’re not as strong? Will they be a bit behind, because they lost some training? I think it’s too early to judge right now.”

Some early returns have actually been positive.

“It’s just been two months or so since we stopped playing,” McAvoy, “so in that way, it’s kind of been like riding a bike. (Skating) comes right back.”

“I actually feel better speed-wise and in other areas than I even did in last year’s camp,” DeBrusk added. “So that’s positive.”

Kuraly said he can “definitely feel the difference” after training less for the coming season, but it doesn’t feel all bad.

“I’m a little lighter than I usually am, but that’s not always a negative,” said Kuraly, who is listed as weighing 212 pounds. “I’m heavy enough. Maybe you lose a little strength, but maybe you’re a step quicker.

“So I think there’s pros and cons to a shorter offseason. You just try to lean on the pros as much as you can.”