Little breathing room exists in the NHL playoffs, and in Game 1 of the Western Conference playoffs at Scottrade Center Tuesday night there was even less.

The Blues dominated the LA Kings for the duration, but somehow the crowd of 17,612 at Scottrade Center could feel that the team’s near misses and spoiled wide-open chances would catch up to the club.

It did.

But in overtime, facing a four-minute LA power play when Kevin Shattenkirk was whistled for high-sticking, Alexander Steen netted a short-handed goal for an abrupt end to a 2-1 OT victory over the Kings.

“It was just such an emotional swing,” Blues coach Ken Hitchcock said. “You’re figuring out who’s going kill a four-minute power play and the next thing the game is over.

“The hockey gods took care of us…they did. We played a great hockey game. Waking up tomorrow would have been a challenge if we didn’t win the hockey game.”

In a turn of events, with Shattenkirk in the penalty box for drawing blood on LA Dustin Penner, it was the Blues who drew first blood on the Kings in the first-round series.

Steen’s second goal of the game with 6 minutes, 34 seconds left in OT gave the Blues a 1-0 advantage in the best-of-seven set and ended the Kings’ eight-game strangehold on the club.

Game 2 is Thursday at Scottrade Center.

The game-winning goal ruined a sensational night for LA goalie Jonathan Quick, who made 40 saves. With the Kings 30 seconds into a four-minute man-advantage, Quick retreated behind his net and was attempting to rim the puck to his right along the boards when Steen accosted him.

The Blues’ veteran, who re-routed to get to Quick, forced a turnover and quickly backhanded the puck into an empty net.

“I just got fortunate behind the net ... it hit my stick,” said Steen, who had just came onto the ice on a line change. “I figured once the puck went down, I had fresh legs. I figured I’d try him.”

It worked.

“It’s exactly what it looked like,” Quick said. “I tried to make a pass. He blocked it and scored. I don’t have an option to the left; you try to make him make a decision. And he got the stick on it.”

The goal ended an overtime in which LA had the upper hand. After being outshot 36-19 through regulation, the Kings ended with a 10-6 shot advantage in OT.

“I thought the overtime, we probably played a little bit not to lose and they gained some confidence from it,” Hitchcock said. “We’re still learning how to win these big games.”

Are they ever.

On a first-period power-play goal by Steen, the Blues were one-half minute away from their first victory over LA since Feb. 3, 2012, when Justin Williams tied the score 1-1 with 31 seconds left in regulation.

Goaltender Brian Elliott, who had orchestrated a quality start to continue his torrid month, was within perhaps one save of his first-career postseason shutout. Williams’ shot went off the stick of defenseman Barret Jackman and over the shoulder of Elliott on the short side.

“They were just throwing bodies at the net and it went off our d-man’s stick and went top corner,” Elliott said. “Anything can happen. You’ve got to be prepared for that.”