One reason playoff hockey is at times almost insanely exciting is the sport’s combination of high skill and utterly essential luck. Everybody recognizes the former. Few want to talk about the latter for fear of offending the gods.

But you want to start any postseason series with the fortunes smiling. You don’t want to lead 2-1 in your own building, with the breaks going your way, then see a fluke flick of the puck from behind the net bounce off the skate of your own defenseman and skip, in a fraction of an instant, past your stunned rookie goalie to tie the score.

Then, with momentum switched, you don’t want to give up a power-play goal just three minutes later and never score again, finally losing, 4-2, after a final empty-net goal.

Scott Hannan was the Washington Capitals defenseman in question, Michal Neuvirth the unfortunate innocent bystander in goal and Steve Downie the Tampa Bay Lighting forward who got credit for the second-period goal because you have to give it to somebody.

“I thought we were in control of the game until the Downie goal,” said Caps Coach Bruce Boudreau after losing Game 1 of this second-round series. “In the end, you get what you deserve.”

“There’s always the element of luck in there,” said Lightning Coach Guy Boucher, speaking specifically of the Bolts’ ability to stop the Caps’ power play. “They could have scored some [more] goals. We’re not kidding ourselves.”

There were multiple reasons for the Capitals’ flat start on Friday night at Verizon Center. The Lightning, despite coming off a seven-game series against Pittsburgh, came out with more energy and grabbed a quick 1-0 lead, taking the first seven shots of the game before Washington even looked fully engaged in the battle.

Some Caps alibied. “They were rolling right into it after their seven-game series. Sometimes it’s almost better that way,” said one player. “After that week off, we were a little rusty,” said another. Though Brooks Laich slapped those excuses into the trash where they belonged, saying, “Anybody will take a rest in the playoffs.”

Also, once the Caps fell behind, 3-2, Tampa Bay’s trapping style of defense, so different from the aggressiveness of the New York Rangers, frustrated the Capitals, though they knew exactly what was coming. “That’s exactly how we expected them to play,” said the Caps’ Eric Fehr.

But, with so much ice yet to cover in this series, perhaps it’s a good time to glance at the mysteries of playoff fortune. Last week, in Madison Square Garden against the Rangers, the Caps won in double overtime in Game 4 to swing the entire series their way. Dozens of times in overtime there was chaos in front of both goalies. But the Caps got the final fortuitous bounce that put the puck on Jason Chimera’s stick two feet in front of the New York net with nothing in front of him but victory. The Rangers deflated.

This time, the first such blow has fallen Tampa Bay’s way. But the Capitals know that, if such things are to happen, better early than late. “We had a lot of pucks laying in the crease,” said Hannan. “A lot of bounces could have gone our way, too.”

We remember the incredibly skilled goals, like the Ducks’ Bobby Ryan turning David Legwand of Nashville into a helpless spinning top on his swerving solo score. But, in direct proportion as our emotions are invested in the outcome, we tend to ignore the degree to which so many postseason goals come unexpectedly out of pure chaos.

Yes, it’s men on skates trying to hit a bouncing flying puck with a stick, so what do you expect, constant precision? But even by the standards of regular-season hockey, the goals of the postseason, which decide series and rip hearts, tend to be doorstep deflections or crazy bounces off a teammate’s skate or heaven knows what nerve-shredding torment.

This game illustrated the point repeatedly and not just in the Lightning’s favor. The Caps started so sluggishly that they perhaps “should” have fallen behind 2-0 just four minutes into the game when Tampa Bay’s Ryan Malone couldn’t get his stick on a bouncing puck in front of a half-open Caps net.

Just seconds later, and the full length of the ice away, the Caps suddenly scored on a careless turnover, a quick Alexander Semin slap shot and a bit of a soft-goal moment by 41-year-old goalie Dwayne Roloson. “He’d [probably] say, ‘Could have got that one,’ ” said Boucher. In a blink, the score was 1-1, not 2-0 Tampa Bay, and Roloson was no longer as hot as any goalie in the playoffs.

The hair’s breadth margins that define postseason hockey recurred all night. The Caps’ Brooks Laich seemed to have tipped in a goal, but it was ruled that he kicked it into the net. No sooner had the Caps gone ahead, 2-1, on a gorgeously executed play off a faceoff, with Eric Fehr netting a pass from behind the goal by Jason Chimera, than Downie’s instant of good fortune materialized.

Downie, from behind the net in the middle of no particularly intense or contested action, merely flipped the puck in front of the Caps’ net hoping that something — dare we say something flukey — would happen. But why should it? Neuvirth was in a fluid rhythm, stopping difficult shots. Why should an innocent random flick of the stick from behind him cause any misery? Yet it did. And the night was never the same.

Good fortune can beget good play. Just 3 minutes 11 seconds later, on a power play, the 21-year-old Tampa Bay superstar Steven Stamkos cashed a classic rebound on the doorstep off a shot by Eric Brewer that Neuvirth couldn’t contain. One minute, a fluke off a teammate’s skate, then, a goal on a tough quality play by Stamkos, in the right place at the right time.

So, would you rather have rest and the favorite’s role on your side? Or in the NHL playoffs, would you just as soon settle for a little luck?

For one night, the latter helped. For a whole series, the jury — or is it those rolling dice of the ice — is still undecided.