The Penguins departed for Tuesday’s contest in Montreal down a man, as Laval, Quebec, native Pascal Dupuis’s doctor visit found cause for concern. After turning in a dominating, 4-0 win over the team with the league’s best record, the Penguins returned home and found out just prior to a Wednesday press conference that they’d lost the player who may well be their heart and soul – almost certainly for the rest of the season, and possibly beyond.

“I’m sorry to report that Pascal had a blood clot in his leg, a deep vein thrombosis, that has resulted in the clot moving to his lung, a pulmonary embolism,” said Dr. Dharmesh Vyas, the Penguins’ team physician. “This is the second such episode. The treatment is at least six months of anticoagulation, or blood thinners, during which time he will not be allowed to participate in hockey [due to] the risk of bleeding with the blood thinners in a contact sport.”

The first occurrence occurred in January, after Dupuis suffered an ACL/MCL tear December 23 and before his surgery in early February. He was on blood thinners for six months as he recovered from the surgery and rehabilitated his knee. This time, it was mild chest discomfort that prompted Dupuis to go in Monday for testing that diagnosed the blood clot in his lung; the results of further tests to investigate the cause were not yet available.

The find was tremendously fortunate for Dupuis and his family – “this could be a life-threatening situation if left untreated,” Dr. Vyas said – but also had the 35-year-old veteran fighting back tears as he acknowledged his hockey-playing future is all but assured. “It’s kind of hard for me to answer that question right now, but I’ll put the effort into it.”

With Dupuis, that much is a guarantee.

For now, the Penguins lose a versatile, top-six forward who has spent the majority of his Pittsburgh career since February 2008 on the wing of captain Sidney Crosby. They lose a player with a storied work ethic who came back from missing most of last season to open this one with 11 points (6G, 5A) in 16 games, shaking off a shot to the back of the neck that caused him to leave the ice on a stretcher to play the next game in the process. They lose one of the most effective pieces of the league’s No. 4 penalty kill, and a contributor on the second unit of the league’s No. 1 power play.

They also lose a highly respected, veteran presence in their dressing room, an impact they’ll try to minimize by proposing a new role to keep him “very involved with the team over the next six months,” said head coach Mike Johnston. “Not as a coach but … he has some time available, so I think we can use him wisely. We’re going to put together some sort of job description in the next week or so and see how he responds to that.”

After such emotionally draining news for a club that has dealt with plenty of it over the past couple of years – a similar blood-clot condition for former backup netminder Tomas Vokoun, a stroke last year for then-26-year-old defenseman Kris Letang and a cancerous thyroid tumor this year for 20-year-old defenseman Olli Maatta – it might not be surprising that the Penguins came out a little flat for their weekend home-and-home with the New York Islanders.

Friday at CONSOL Energy Center, the young, hardworking Islanders responded to Pittsburgh’s first-shot goal by not surrendering another shot until 12:30 of the first. The Isles built leads of 3-1 and 4-2 before the Penguins found their legs and rallied to a 4-4 tie, with goaltender Marc-Andre Fleury uncharacteristically falling short in the shootout in what could have been his 300th career win. New York also managed to stay out of the box to keep Pittsburgh’s league-best power play from getting even a single opportunity.

“The first period, we didn’t really give ourselves a chance with the way we played; for whatever reason, we didn’t play well at all. They carried the play and got rewarded for it,” Crosby said. “We were able to get ourselves back in the game, but we just didn’t play a full 60 minutes and didn’t really deserve to win.”

The Penguins got the better start they were looking for Saturday on Long Island, but it quickly became all New York. The Islanders won puck races and battles, capitalized on Pittsburgh’s mistakes – including Steve Downie’s ill-timed penalty in a one-goal game midway through the third – and beat them at their own puck-possession game to win, 4-1.

“We were a lot better than last night in our start, [but] I thought, as the game went along, they took over getting pucks to the net and also finding those loose rebounds that are there,” Johnston said. “That’s what you try and do by creating shooting pressure, and we didn’t do it enough.”

“We weren’t able to get control enough,” Crosby said. “They carried the play in the offensive zone and, by the time we ended up having to make plays, I don’t think we had enough energy based on having to spend most of the time in our own end.”

The Penguins will explore the market for a top-six winger – something they might have been doing even before Dupuis’ medical situation – but, with a 13-4-2 record that has them at third in the Eastern Conference and tied with the Islanders atop the Metropolitan Division, there’s no need to rush into a move.

For now, they’ll look to rebound with the personnel they have Monday against a Bruins team that’s been playing good hockey, going 7-3 in their last 10 contests. The Crosby line might stand to rebound in Boston, against whom winger Chris Kunitz has a nine-game, nine-point streak.

“You’d like to get scoring throughout your lineup, but we also need Sid, Kuni and [Blake Comeau] – they’re under checking pressure, but they’ve got to break through a little bit,” Johnston said.

“We didn’t do a good enough job [against the Islanders],” Crosby said. “Bottom line is, we need to get better.”