PITTSBURGH -- With at least one veteran defenseman departing, the Pittsburgh Penguins will rely heavily on Derrick Pouliot to take a substantial step forward this season.

It's a step the second-year defenseman said he is prepared to take.

"I definitely know the expectations, that's for sure," said Pouliot, Pittsburgh's first-round pick (No. 8) at the 2012 NHL Draft. "I know I have to be ready when the season comes around, what I have to do to be ready. It's a little different in that aspect, that's for sure. … I'm pretty anxious. I feel like I can take on a bit of a bigger role."

Pouliot, 21, impressed in his first season in a similar fashion to defenseman Olli Maatta's debut during the 2013-14 season. In 34 games, Pouliot solidified his position as one of Pittsburgh's top four defensemen (two goals, five assists) while showcasing his dependable defensive IQ, steady skating and heavy slap shot, which he routinely unleashed on the Penguins' second power-play unit.

He temporarily filled a void left by Maatta when the 20-year-old defenseman sustained a season-ending upper-body injury 20 games into his second season and about two weeks after returning from surgery to remove a cancerous tumor from his thyroid.

Maatta is expected to return this September when training camp opens. But even with him back in the lineup, Pouliot's presence will be necessary for Pittsburgh's success.

Paul Martin, arguably the Penguins' most consistent defenseman the past three seasons, signed with the San Jose Sharks on July 1, and defenseman Christian Ehrhoff, who signed a one-year contract with Pittsburgh last summer, is an unrestricted free agent and unlikely to return.

Martin played a lot of minutes during his five seasons in Pittsburgh, with a high of 25:20 per game in 2012-13 and a low of 22:47 last season.

"Someone's going to have to step up and take some of those minutes that he took," Pouliot said. "He played a lot. He's a very good defenseman, so there's a chance for everybody to grab an elevated role."

Rob Scuderi will again provide veteran leadership on the back end, but the top-four group will be led by 28-year-old defenseman Kris Letang, who is likely to be paired with Maatta. Pouliot's partner won't be established until September at the earliest, but he is firmly entrenched as one of the Penguins' necessary cogs.

The defensive depth Pittsburgh built throughout the past several seasons will finally be tested with Pouliot, Maatta and potentially Brian Dumoulin all finding a place in the opening-night lineup, if not in the Penguins' top-four defense group.

Pouliot's place within that group wasn't guaranteed entering July when he was rumored to be a piece in a potential trade for Toronto Maple Leafs forward Phil Kessel. The trade went through on July 1, but Pouliot remained with Pittsburgh.

"I heard some rumors that I might be involved in that," Pouliot said. "I saw the trade come through and I think that's great. He's a very good player. He scores a lot of goals. I think he'll be a good fit here. … You try not to think about [being traded]. I was working with [former Penguins forward Gary Roberts] in the summer. You just kind of go day by day.

"If it happens, it happens. And fortunately, it didn't happen and I get to stay here."

Pouliot contacted Roberts shortly after the New York Rangers eliminated the Penguins during the Eastern Conference First Round of the 2015 Stanley Cup Playoffs. After sustaining an upper-body injury that kept him from making his postseason debut, Pouliot set out to enter the 2015-16 season in better condition and felt Roberts could help him achieve his goal.

"I improved my fitness over the summer," Pouliot said. "That's a big thing, so I can handle the speed. And the minutes aren't really elevated, I think, but they're harder minutes. I think that'll be a big help coming into this season.

"One of the big things I learned, I think I have to be in a little better shape. I learned I can play at the NHL level and hopefully I can stick and be a big part of this team in the coming years."

Pouliot is attending his fourth development camp with the Penguins this week. His experience is clear when compared with Pittsburgh's prospects.

Wilkes-Barre/Scranton Penguins goalie Matt Murray, the 2015 AHL goaltender of the year and rookie of the year, faced Pouliot during a shootout competition on the opening day of the development camp Tuesday. Pouliot drove in slow, drifted left and quickly shifted the puck from forehand to backhand before roofing it over Murray.

"I don't want to pump his tires too much, but he's a heck of a player, obviously," Murray said. "He definitely stands out out there. He's just so smooth. His offensive ability is just God-given talent. He's born to be a hockey player and he's really fun to watch. Not so fun to try to stop, most of the time."

Pouliot is no longer using the camp to develop his game; that was accomplished in previous years. This time, he is expected to help guide the next wave of Penguins talent.

"He's at a stage of his career where nobody should be dragging him around to meetings or to the rink," Penguins assistant general manager Tom Fitzgerald said. "He should be leading. I don't know who I put him with, but I'm guessing I put him with a young 18-year-old to help get up, be prepared to get to the rink. Not just roll out of bed and throw a baseball hat on.

"That's the stage he's at. And his ultimate goal, obviously, is to make this team out of training camp."