The physical nature of this series has taken its toll on the Blues and Wild and their coaches

This is the third playoff series in two seasons that has taken Wild fans through wild swings of emotion, from joy to anger to satisfaction to regret.

Wild players and coaches, too.

In five games of the team’s series with the Blues, the Wild has, in turn, played spectacularly well in a victory, played well but lost close, dominated, failed to show up and overcome a slow start.

Same team. Same coaches. Same players. Same opponent. Yet in every game, the Wild has played like a different team. So has St. Louis.

The enduring randomness of sports explains the variance to a degree, but Blues coach Ken Hitchcock offered a more detailed and relevant explanation on Friday.

Hitchcock has won a Stanley Cup. He ranks fourth in NHL history with 708 victories. Even he isn’t sure he’s seen so much effort expended on checking in a playoff series as he has during the last week.

“Both teams, I’ve never seen shift lengths so short in my life, since I’ve been coaching in the NHL,” Hitchcock said after the Blues’ morning skate. “From the opening buzzer to the end of the game, shift lengths are in the 30s [seconds]. I’ve never seen that before. Usually, you get it down there in the third period, but this opens the game. That’s how much is being put into each shift by each player.”

In each game, the team that has scored first has won. Wild star Zach Parise attributed that trend to the emotional impact of the first goal. “It’s really important to your attitude on the bench, and in the locker room,” he said. “But you also have to be able to overcome that.”

Wild goalie Devan Dubnyk, like Hitchcock, attributed the importance of the first goal to the ability of both teams to play a relentless checking game.

“It’s tough to climb back into the game when you have two teams that are not just capable defending in their own end but defending by having the puck at the other end,” Dubnyk said. “You look at both teams, we play similar, we have a similar game plan that’s aggressive and pressuring.

“You’ve seen it. It can be exhausting and overwhelming for the other group when one group is doing it as well as they are. Both teams are built to play that way. That’s why it’s an exciting series, and that’s why I don’t think anybody expected it to be a short one.”

The game’s human element is most exposed during playoff hockey, when emotions rule.

“You take your foot off just a little bit and the other team is ready to pounce and go at it,” Hitchcock said. “It also happens when you have so many players who are so similar. Mike [Yeo] uses four lines, we use four lines, so there’s no breathing room, there’s no space. … It’s just all-out short shifts, get off the ice.”