There is a strange and insidious epidemic spreading across the continent – it affects hockey players, often in the third period.
Good teams, not-so-good teams, it doesn't matter; almost everyone has fallen prey to the mystery ailment of the two-goal lead.
According to Elias Sports Bureau, there had been 11 multigoal comeback wins in 53 playoff games heading into Sunday evening's action; the most recent being Boston's 5-3 weekend triumph over the Montreal Canadiens.
"Worst lead in hockey, pretty much," said Bruins goalie Tuukka Rask. "Especially if you're the road team, you're up by two and the home team gets one and gets the crowd behind them and never looks back."
Note that Rask said "worst lead," not "most dangerous."
The stats are clear: The most ephemeral lead in hockey is one goal, which is erased in nearly 85 per cent of cases.
According to a 2011 full-season analysis by Patten Fuqua, a blogger who primarily writes about the Nashville Predators, on average teams rally to tie from two-goal deficits 40 per cent of the time.
It's happened to a bevy of other teams (including reigning Stanley Cup champion Chicago on Friday), and on the six occasions the Canadiens have taken two-goal leads in these playoffs, only twice has the lead held up to the end of a game.
Deeply weird stuff tends to happen when the Habs and Bruins collide in the postseason, so it did again Saturday.
After holding the Bruins to one shot on goal through the first 10 minutes of the third, they allowed three goals in just over five minutes and ultimately lost 5-3.
It was the first time this season the Habs lost in regulation after taking a lead into the third period, a span of 43 games.
The good news is the series is tied heading into two straight at the Bell Centre – as coach Michel Therrien said, "if we would have said that at the beginning of the series we would have been very satisfied."
Theories abound as to why teams have had such trouble protecting leads in these playoffs; the Habs' Josh Gorges offered a popular one in a conference call Sunday.
"I think it just shows that all teams are competitive … no lead is ever safe because the other team is not going to quit," he said.
It's also true that teams tend to lapse into conservatism, and give up more scoring chances as the opposition's desperation mounts.
In the Habs' case, there may also be tactical issues to iron out in the defensive zone.
Though they have given up an NHL-high 13 third-period goals in the playoffs to this point, Montreal isn't a terrible third-period team (they were sixth-best in terms of goals allowed in the frame during the regular season).
It's just that Boston is an elite one.
And in both games of their second round series to this point, they have keyed the comebacks in similar circumstances.
In game one, Reilly Smith's innocuous shot from the right corner found the net through a crowd, in game two Patrice Bergeron scored from essentially the same spot, assisted by a carom off Francis Bouillon.
Both times, Boston's next goal came on long shots from the middle through a forest of players.
Therrien suggested Sunday that as much as anything his team has been unlucky – "you need breaks to win games, and when you look at Bergeron's goal the puck took a bad bounce in front and went over the shoulder of [goalie Carey] Price."
"If you analyze the third period in the first 10 minutes, they only had one shot on goal, so I don't think we were a team that was sitting on a lead. We were putting a lot of pressure on the puck carrier and we were in complete control," he said.
So what went wrong?
Their luck turned, certainly. But the same thing has happened in each of their last three games; the sagging Habs defence allowed goals by defencemen shooting through screens from the high slot – Matt Carle in game four against Tampa Bay, Johnny Boychuk in Game 1 in Boston, Dougie Hamilton in Game 2.
The simplest remedy, Gorges said, is to keep the puck at the other end of the ice.
"We have to do a better job of getting to that puck first," he said.
It's easier said than done against the Bruins.
Sunday was a day off for the Habs' players, but Therrien alluded to the coaches scrutinizing the video from the first two games to see what adjustments will need to be made.
It will help that Montreal will have last change in the next two games, allowing the Habs a better opportunity to choose their match-ups, particularly with their defensive pairings.
"I'm approaching this with a lot of confidence, to be honest. We managed to take the lead. Boston showed a lot of character to come back in both games, but we still took that lead," he said.
The most encouraging news of all: First-round anthem singer Ginette Reno is expected to be available for Game 3.
Whether she sings or not, it promises to be a loud evening.