The challenges facing the Bruins in the first couple of months of the season are well-known. They are expected to be without Brad Marchand and Charlie McAvoy until around Thanksgiving while Matt Grzelcyk will be sidelined to start the season as well.

Facing part of that challenge head on will be the team captain and longest tenured Bruin, Patrice Bergeron. Since the middle of the Stanley Cup season of 2010-11, Marchand has ridden shotgun on Bergeron’s left side, with tremendous results. They’ve had different right wings over the years, from Mark Recchi to Tyler Seguin to Reilly Smith to David Pastrnak to Jake DeBrusk, but the Bergeron-Marchand partnership has been a constant for over a decade.

Marchand underwent surgery and labral repair on both hips in May. The recovery timeline is six months, which would put a return around November.

Bergeron, speaking to reporters on the first day of captain’s practice at Warrior Ice Arena on Monday, acknowledged the test he’ll be facing.

“It is going to be an adjustment,” said Bergeron, who is skating this week and expects to be 100 percent by the start of camp after undergoing elbow surgery in the offseason. “The two of us, it’s become second nature at this point. We read and react from each other. We know where each other is going to be on the ice, pretty much at all times. It does make things easier. That being said, you’re playing with some great players, some players with a lot of talent with great vision and hockey sense. It’s for me to adjust, but also for us, whoever I’m playing with, to communicate and talk and find ways to make that transition as seamless as possible.”

Taking Marchand’s place, at least to start training camp next week, will be newcomer Pavel Zacha. Obtained in the offseason for Erik Haula, the 2015 sixth-overall pick would seem to have higher offensive ceiling that what he had shown in New Jersey. A solid two-way player who can play both wing and center, Zacha had his highest point total last season with 15 goals and 21 assists in 70 games, though two years ago he had a career high in goals with 17 in 50 games.

“He’s a great player, a very smart player,” said Bergeron. “It’s something I knew even before he came in. He plays the game the right way. He’s always well-positioned. He’s got a great shot and, even from talking to him, he wants to (develop) a bit of a shoot-first mentality a little bit more than he’s had in the past.”

Zacha, 25, makes his offseason home in the Boston area and has been working out at Warrior Ice Arena for a while. He’s looking forward to the chance he could be getting in the first couple of months of the season possibly playing alongside a future Hall of Famer.

“I think I’ve been lucky enough to be here for a couple of weeks now so I’ve gotten some one-on-one talks. Just being around him and seeing his work ethic and his thinking around the game is great. It’s been a good couple of weeks here and I’m just excited about what’s going to happen going forward,” said Zacha.

The Haula-for-Zacha deal looks like a good one for the Bruins. Haula had done a good job when he was moved into the center spot between Taylor Hall and David Pastrnak, but he was not able to give the team much when he played wing and further down the lineup. That spot between Hall and Pastrnak will now go to the returning David Krejci.

The hope, if all goes well, is that the 6-foot-3 Zacha will be able get a career boost from playing with Bergeron and then seamlessly drop down to play with Charlie Coyle once Marchand is healthy, giving the Bruins a more potent third line. A big focus for Zacha is to pull the trigger on more shots. Last season, he average just over two shots a game.

“I think especially now, playing with him or playing around guys like that, (I’m) trying to shoot more pucks, trying to change the mindset, just watching little videos when I had the opportunity to do that,” said Zacha. “That’s something he wants me to do, too, so I’ll focus on that even more going forward while I’m practicing and playing with him. I’m excited for that.”

JAKE DeBRUSK met reporters this week at Warrior Ice Arena for the first time since rescinding his trade request under which he played all of last season. He never fully explained his reasons for the request, though it was easy to assume a big part of it was an issue with Bruce Cassidy, the former Bruins’ coach who had found it necessary to sit the young winger on occasion.

That belief was only fortified when, after Cassidy was fired, DeBrusk and his agent let GM Don Sweeney know that he no longer wanted to be traded. That the change behind the bench had a lot to do with DeBrusk’s change of heart seemed so obvious it didn’t need to be spelled out, and DeBrusk passed on doing so.

“Hey, it’s been speculated enough, I think,” said DeBrusk. “You guys know I see stuff and obviously that’s an easy answer. … Obviously it’s one of those things that’s interesting and it’s a hot topic on why I even asked for a trade, but I am just looking forward to this year. … It’s one of those things where that’s in the past and this whole summer’s been focused on getting right and getting ready for the season and that’s kind of how I view that question.”

DeBrusk did credit his teammates for sticking by him despite the trade and not letting the issue be one that poisoned the dressing room.

“At the end of the year I said I’d talk to my family and think things over. I think the biggest thing, honestly, was the support I got from the guys in this room last year,” said DeBrusk. “That’s something I’ve always loved about this team. I love the boys, and also the city and everything else.”