BOSTON — They’ve been here before, in several ways:

Playoff series against an upset winner? Check.

Playoff series against a better-rested opponent? Check again.

Playoff series against a team that relies on speed and an active defense corps to generate offense? Check once more.

If the Bruins handle all that as well as they handled the Maple Leafs in Round 1 and the Blue Jackets in Round 2, they’ll be Stanley Cup finalists.

First, though, there’s the matter of beating the Hurricanes four times in the best-of-seven Eastern Conference final, which begins tonight at TD Garden.

“I think there are going to be some unique challenges,” said general manager Don Sweeney, who spoke on behalf of the team on Tuesday at Warrior Arena while Bruce Cassidy and his coaching staff formulated a game plan.

“(The Hurricanes) are a strong forechecking team. They get on you, and they (back check) on the puck. Their goaltending has been excellent. ... We’re going to have to be at our best.”

The Bruins learned Tuesday evening that they’d face another unique challenge at the start of the series, this one from within. The NHL’s Department of Player Safety suspended defenseman Charlie McAvoy, the Bruins’ ice time leader (24:46 per game) and No. 2 man on their plus-minus list at plus-8 through 13 games, for Game 1 of the series, the result of McAvoy’s illegal check to the head of Josh Anderson in Game 6 against the Blue Jackets on Tuesday night.

They did know, however, that they’ll be facing a team with a “why not us?” attitude and enough belief in itself to pull off two largely unforeseen series victories.

The Hurricanes needed more time to pull off their first-round upset than the Blue Jackets, who swept the Presidents’ Trophy-winning Lightning. But rebounding from an 0-2 deficit to eliminate the defending Stanley Cup champion Capitals in seven games — taking Game 7 on the road, in double overtime, at that — was no small feat for Carolina. The wild-card entry then proceeded to beat the Islanders at their own stingy game with two straight wins in Brooklyn (1-0 in overtime, 2-1 in Game 2) before completing a four-game sweep with a pair of 5-2 decisions at PNC Arena, where they’re 5-0 this postseason.

The Hurricanes have shaken off some adversity, too.

Goalie Petr Mrazek, who effectively survived Round 1 against the Caps (2.53 goals-against average, .899 saves percentage) seemed to be finding more of a groove early in the Islanders series, but had to leave Game 2 with a lower-body injury. Journeyman Curtis McElhinney, whom the ‘Canes acquired on waivers from the Maple Leafs at the start of the season, stepped in to close out that game, and the series. McElhinney, 35, had made only two previous playoff appearances — one with the Flames in 2008-09, the other an ineffective relief job (four goals on 23 shots) for the Leafs in Game 2 of last year’s first round against the B’s.

The Bruins, who opened their series against the Blue Jackets 48 hours after eliminating the Leafs, get only a single practice session to get ready for the Hurricanes, who haven’t played since last Wednesday.

“They’ve got some juice,” Sweeney said.

The B’s, who have generally been missing a player or two per game because of injury or illness throughout the postseason, enter the conference final the same way. Winger Noel Acciari is day-to-day with an upper-body injury. Defenseman John Moore, who has played only four of 13 games because of an upper-body injury, is “available,” Sweeney said, but “dealing with stuff that makes it hard.” Defenseman Kevan Miller, who suffered a knee injury in the next-to-last regular season game on April 4, has “made some progress,” according to the GM, but Miller hasn’t started skating yet.

“We’ve got a tough challenge in front of us,” Sweeney said. “So we worry about Game 1, then move on.”