PITTSBURGH -- Through the first two rounds of the Stanley Cup Playoffs, the Pittsburgh Penguins have been good enough to overcome just about any deficit. But it's been quite the opposite through two games of the Eastern Conference Final.

Pittsburgh trails the best-of-7 series, 2-0, against the Boston Bruins in advance of Game 3 Wednesday night at TD Garden (8 p.m. ET; NBCSN, CBC, RDS). A big reason is the Penguins have been trailing in games early and often.

"Very early on [Monday] night, we got behind by a goal and then the second goal ... and we got off our game plan," Pittsburgh coach Dan Bylsma said after practice Tuesday. "We got off our individual games by trying to get back a goal or goals by one play, by one instance, by one situation, and it got us off a path and we deviated from the game plan in an effort to do so."

The Penguins have been behind for all but 8:51 of the first two games of the series. They have never held a lead against the Bruins.

That is in stark contrast to the way the first two rounds of the Stanley Cup Playoffs went for Pittsburgh. In 11 games against the New York Islanders and Ottawa Senators, the Penguins entered 25 intermissions following the end of a period or overtime session without the game having ended yet -- they trailed heading into two of them.

So far in the conference final, Pittsburgh has yet to retreat to its locker room facing anything other than a deficit against Boston.

"We made some mistakes," Penguins defenseman Matt Niskanen said about the Bruins taking a lead 28 seconds into Game 2 Monday heading to a 6-1 win. "We get down in a hockey game, and guys are trying to make something good happen and get us back into it. And that's when things don't go so well."

Though this particular Penguins team might not have much experience coming from behind in a playoff game, the franchise has proven to be one of the best at overcoming a series deficit. Five times since 1991, the Penguins have overcome a 2-0 series deficit to advance.

The two most recent instances came in their Stanley Cup season of 2009. Most of the core of the current Penguins were on that team that lost the first two games against the Washington Capitals in the Eastern Conference Semifinals and against the Detroit Red Wings in the Stanley Cup Final before coming back to win each series in seven games.

"Of course that helps; we have great experience," Penguins center Evgeni Malkin said. "It's a different time and a different team, but we know we can come back. We've seen Chicago come back from down 1-3 and win three games [this season], so we know it's not over. It's the playoffs, it's tough, it's a tough situation, but it's not over yet."

Pittsburgh went through an almost hour-long practice Tuesday on a day that typically might have been an off day or reserved for an optional skate if the series were tied or the Penguins were coming off a win. Captain Sidney Crosby said there weren't many tactical adjustments discussed.

"I don't think it's anything to do with X's and O's," Crosby said. "We didn't execute [in Game 2]. That's really what it came down to."

Crosby remembered each of the 2009 comebacks, during which the Penguins won Games 3 and 4 each time. They won those games on home ice, so they recognize the task is more difficult having to travel to Boston for virtual must-win games this time. But going through it twice before provides a blueprint.

"Play with that amount of desperation that you need to going down, 0-2," Crosby said. "We've got to make sure we bounce back and don't allow the first two games to frustrate you and just stick with what's gotten us here.

"We still haven't played our best game yet. We'll strive for that [Wednesday]."