They were the most consistent team in the conference by a sizable margin during the regular season, and few thought that the Bruins would be able to defeat them in a seven-game series.
The Penguins' mighty offense, the best in the NHL during the regular season and the hottest in the postseason through two rounds, was held to just two goals.
The shock will wear off quickly for general manager Ray Shero, who must come up with a workable plan for the 2013-14 season and beyond.
(All salary figures are courtesy of CapGeek.com.)
Evgeni Malkin is the most dangerous No. 2 man in the league. On many nights, he is the best player on the ice even though Sidney Crosby is out there with him.
Crosby and Malkin are the two engines on the Penguins. They give the team best 1-2 punch in the league.
Malkin is entering the last year of a contract that pays him $8.7 million per season. There have been rumors that the Penguins might trade him, but longtime Pittsburgh Tribune-Review columnist Rob Rossi debunked that myth, saying that Shero has been told to keep the team's two stars together under any circumstances.
Malkin is a two-time NHL scoring champion, a Hart Trophy winner and a Conn Smythe Trophy winner. Ideally, he will sign an extension before the team reports to training camp in September. If the Penguins can keep him at his current salary level—which is the same amount that Crosby earns—the Penguins should consider themselves lucky.
Malkin may have been held scoreless by Tuukka Rask and the Bruins, but he is one of the most gifted players on the planet, and the Penguins must keep him.
Penguins goalie Marc-Andre Fleury has had disappointing playoff performances two years in a row.
That's something that Shero cannot ignore during the offseason. After an embarrassing performance against the Philadelphia Flyers in the 2012 playoffs with a 4.63 goals against average and an .834 save percentage, Fleury struggled again this year in the postseason.
The Penguins' starting goaltender had a 2-2 record in his four starts for the Penguins before he was pulled in favor of Tomas Vokoun. Fleury had a 3.52 GAA and an .883 save percentage in this year's playoffs.
When he finally returned to action in Game 2 against the Boston Bruins as Vokoun's relief, he looked shaky and unsure as he faced 17 shots and gave up three goals.
Fleury was solid during the regular season—he had a 23-8-0 record, 2.39 GAA and a .916 save percentage—but he has lacked dependability in two consecutive postseasons.
How can the Penguins remain confident in Fleury? He may have made key save after key save in their 2009 Stanley Cup championship, but he appears to have lost his magic.
Trading Fleury and his $5 million salary may be quite difficult for Shero, if the general manager chooses to go that route.
Pascal Dupuis, Matt Cooke and Craig Adams are all key role players with the Penguins who have been with the team dating back to their Stanley Cup victory in 2009.
All will be free agents in July, and the Penguins will almost certainly be forced to make difficult choices. There's no way Shero can bring back all three of those key players.
The Penguins have salary commitments of $56.4 million heading into the 2013-14 season. Since they are just $7.9 million under next season's salary cap of $64.3 million, it means that Shero can't bring back all of these longtime Penguins mainstays.
Dupuis scored 20 goals during the lockout-shortened regular season, and he had seven goals in the postseason. It would seem that Dupuis would be the most valuable of those three free agents.
Cooke is a high-energy player who has a long history of controversial hits, while Adams is an aggressive and hard-hitting player who is more likely to change a game with his body checking than he is with his goal scoring.
Defenseman Kris Letang is a finalist for the Norris Trophy this season. He is considered one of the best offensive defenseman in the league because of his speed and lethal shot. He scored 38 points this season and a plus-16 rating.
Brooks Orpik is a hard-hitting and dependable defenseman who can bang bodies, carry the puck and keep his cool in the defensive zone. He has a plus-36 rating over the last two seasons.
Left wing Chris Kunitz has proven to be a dependable scorer. Kunitz scored 26 goals in 2011-12, and he followed that up with 22 goals this season. He has a hard shot with a quick release.
All three will be in the final years of their respective contracts in 2013-14. Shero certainly doesn't want to let them get away, and this could be an important offseason to get them under contract.
If any or all of those players don't sign extensions during the summer, they could opt to test the free-agent market in the summer of 2014.
That would not help the Penguins secure their long-term future.
When Iginla chose the Penguins over the Boston Bruins as his trade-deadline destination, Boston general manager Peter Chiarelli joked that the Penguins were a Stanley Cup "lock" because of the fine-tuning they had done to their roster.
If the Penguins had won the Stanley Cup, Shero might have tried to get one or more of the trio to return. However, all three are free agents, and there doesn't seem to be a compelling reason to bring any of them back.
The Penguins have plenty of salary-cap issues, so it seems all but certain that Iginla, Morrow and Murray will hit the free-agent market in July.
Sidney Crosby is unquestionably one of the most dynamic players in the NHL.
He was on track to run away with the scoring title (56 points in 36 games, according to Hockey-Reference.com) and was the likely Hart Trophy winner before suffering a broken jaw and several shattered teeth when he was struck by a deflected puck with 12 games to go in the regular season.
He displayed guts and desire in coming back with a full face shield in Game 2 of the opening round of the playoffs against the New York Islanders. Crosby scored 15 points in his first 10 postseason games and was improving each time out—until the Penguins ran into the Boston Bruins.
Crosby was held scoreless in the four-game sweep. His frustration appeared to get the best of him in Game 1 when he got into a useless pushing match at the end of the second period with Bruins behemoth defenseman Zdeno Chara.
Crosby then played what many consider to be the worst game of his career in Game 2 of the series when he had four giveaways and was minus-one for the game.
Why was Crosby so frustrated after two periods in the first game of the series? That seemed to be an overreaction to a 1-0 deficit.
Crosby's reputation also took a hit in last year's playoff loss to Philadelphia, when he behaved more like an agitator instead of a superstar.
Added maturity would appear to be a characteristic that would help Crosby in the years to come.
Dan Bylsma was behind the bench when the Penguins won the 2009 Stanley Cup by beating the Detroit Red Wings in the seventh game of the Stanley Cup Final.
Even though the Penguins have been considered the most talented team in the NHL for the majority of ensuing four seasons, the Penguins are 20-21 in the postseason since then.
Shero stopped talking about his team's future in the final days of his team's stay in the playoffs. He did not give Bylsma a vote of confidence, according to an article by Rob Rossi of TribLive.com, to remain as head coach of the Penguins.
That does not mean Bylsma will be fired. But he almost certainly will have to defend himself to Shero and owner Mario Lemieux if he is going to retain his job through 2013-14.