Colorado Avalanche players were thrilled for center Darren Helm after he scored the series-winning goal in his side's 3-2 victory against the St. Louis Blues with just five seconds remaining in regulation.

With their Game 6 triumph away from home, the Avalanche secured a 4-2 series win, and will now play the Edmonton Oilers in the Western Conference Finals, with the winner earning a chance at the Stanley Cup.

It was far from a comfortable win for the Avalanche, needing to come from behind twice.

Firstly, after Justin Faulk gave the Blues a lead in the first period, Colorado's J.T. Compher equalised five minutes into the second frame.

That tie would last less than five minutes before Jordan Kyrou got on the end of a build-up by Andre Burakovsky and Josh Manson, making it 2-1 for the home side, and that score would hold through the second period and the first 10 minutes of the last.

After a penalty gave the Avalanche a power play, Compher capitalised with his second goal of the game, tying things up with just under 10 minutes to play.

With both teams pushing for a late winner, it would be the away side to produce the breakthrough, as Helm found his way past Blues goaltender Ville Husso in the dying seconds to deliver the series win to the Avalanche.

Speaking to post-game media, Avalanche forward Gabriel Landeskog said it was a joy to see Helm be the hero, scoring his first goal of the postseason when his team needed it most.

"There's no other guy that deserves it as much as he does," he said. 

"You talk about his work ethic, but he's the guy that comes to the rink with a smile on his face, gets along with everybody."

Colorado goaltender Darcy Kuemper shared similar sentiments, calling it "a super-clutch goal".

He added: "It's always fun to see someone like Darren, who plays the game so hard, (but) always doesn't get rewarded with the points – to come up with a big goal like that is really special."

Avalanche coach Jared Bednar said he could tell from the jump his side was up for the challenge, and that there is still plenty of work to do.

"From the drop of the puck, we were ready to go," he said. "You could tell the belief was there."

"We're only halfway to our goal... we're just getting started."

The Blues were left licking their wounds, convinced they side were good enough, but just failed the test.

"We feel like we're a good team and we let that series slip," Blues center Brayden Schenn said.

St. Louis coach Craig Berube added: "It's tough, a tough way to end it. That's the way it goes. Our guys battle hard."

Blake Coleman was left questioning his own understanding of the rules after his go-ahead goal against the Edmonton Oilers was controversially disallowed as the Calgary Flames' season came to an end.

Coleman looked to have given the Flames a 5-4 lead in Game 5 of the second-round series when he followed in after Mikael Backlund's effort was initially repelled by Mike Smith.

However, a video review ruled Coleman had deliberately kicked the puck into the net.

The game was subsequently sent to overtime, with Connor McDavid scoring the winning goal for the Oilers as they clinched a 4-1 series victory to progress to the Western Conference Finals.

NHL rule 49.2 says a player cannot use "a deliberate kicking motion" to divert the puck into the net, however, Coleman appeared to turn his skate to help himself stop before making contact with the puck. Additionally, Backlund's effort looked set to cross the line despite Smith's block.

Yet the officials still ruled against Coleman, who could only express his bemusement after the game.

"I don't think I understand the rule," he said. "Getting pushed, just trying to keep my foot on the ice, I haven't watched it enough but in live speed, felt like I was in a battle.

"My understanding is you can direct the puck, you just can't kick it. I didn't feel like I kicked it but can't go back and change it now. It is what it is.

"It's unfortunate that was such a big part of the game and happened the way to influence the way it all went down. Aside from that, proud of our team, we fought hard, I wish that would've helped put us over to another game.

"There's no intent, just trying to get there, my understanding is you can redirect the puck off your foot as long as you're not lifting it and kicking it into the net.

"I'll go watch it again, maybe it's glaringly obvious and I just didn't feel like I did what it looks like."

Interim Edmonton Oilers head coach Jay Woodcroft praised his team's resilience in difficult circumstances after defeating the Calgary Flames 5-4 in overtime to reach the NHL's Western Conference final.

In a Battle of Alberta that saw an extraordinary 46 goals in five games, Connor McDavid scored at 5:03 in the extra period as the Oilers won their series 4-1.

The Edmonton captain scored his seventh goal of the playoffs, beating Jacob Markstrom off a pass from Leon Draisaitl to score the winner, while Zach Hyman contributed a goal and two assists.

Taking over from Dave Tippett in February, Woodcroft asserted his belief in the Oilers locker room post-game.

"There were some things that we could clean up heading into overtime," he said.

"We talked about that, but I think with our group there is a measure of calm and composure, and a strong belief that we have the people in the room that can get us through any type or circumstance, so we felt good about our chances.

"When I walked into that room at the beginning of February, I was bullish on our players because I saw a sincere desire to win and not just the desire to win, but I saw people willing to pay the price to win.

"We always felt that we had the ability to score. For us it's sometimes not just about what we're getting but also what we're giving up and as the series went on we got better at that."

McDavid now sits fifth in NHL history for playoff points per game at 1.45, while Draisaitl's 17 goals over the five games beat Wayne Gretzky's 1983 record for most points in a playoff series between the two teams.

Game-winner Tyler Bozak said the St. Louis Blues were not ready to go on holidays after they pulled off a stunning 5-4 comeback in overtime against the Colorado Avalanche to keep their season alive.

With the win, the Blues still trail 3-2 in the series, but they earned a chance to head home to St. Louis for Game 6

The Avalanche looked all set to move on to the next round after a pair of first period goals to Nathan MacKinnon, and a second-round strike from Gabriel Landeskog had them up 3-0 at the halfway point.

Instead of lying down, the Blues fought back in front of the raucous Avalanche crowd, with Vladimir Tarasenko pegging one back to make it 3-1 at the end of the second period.

The Avalanche were able to hold things together for the first nine minutes of the last period, until the Blues' pressure started to pay off, with Robert Thomas trimming the margin to 3-2.

Jordan Kyrou would have thought his goal would send the game to overtime as he made it 3-3 with less than five minutes to play, but the Avalanche answered straight back as MacKinnon finished off his hat-trick with under three minutes on the clock.

But there would be another twist to the tale, as Thomas was able to force home his second goal, the equaliser, with 56 seconds remaining in regulation.

Overtime only lasted 3:38 before Bozak silenced the home fans with the golden goal to keep the Blues' Stanley Cup dreams alive.

Speaking to post-game media after scoring the winner, Bozak said his side was not ready for things to end this way.

"Just a resilient group of guys," he said. "[We] got down, [but] didn't want the season to be over.

"[We] fought hard and got some big goals late. I just got a little bounce up top and saw a lane to the net. 

"In overtime, there's definitely no such thing as a bad shot. I just tried to get it through on the traffic – all I know is that it went in, and that's all that matters."

Blues coach Craig Berube highlighted the gutsy effort to come from behind twice.

"We battle back, and then we give up that goal," he said. "It could have been deflating, but our guys have a lot of guts.

"Guys battled and kept battling. That's really what it boils down to. 

"We didn't get off to the start we wanted, being down quick. I thought the second half of the second period we started to come with our game.

"Getting to the goal line, winning battles down there. We went north. That's what it boils down to."

Thomas had not scored in any of the Blues' first 10 playoff games, but said it was nice to break the drought.

"Better late than never, I guess," he said.

"You've got nothing to lose – you might as well throw it all out there. That was the mindset."

The New York Rangers are feeling confident about their prospects of reaching the NHL Stanley Cup Finals after fighting back from 2-0 to square their series with the Carolina Hurricanes, earning a 4-1 win on Tuesday.

The Hurricanes have had the wood over the Rangers in recent times, winning eight out of their previous nine encounters prior to the past two meetings in this heated series.

Rangers center Andrew Copp, who scored a goal with two assists in the Game 4 win, said the momentum was with his side after winning 3-1 in Game 3.

"We're confident," Copp told reporters. "We get two games where we win, we play well, we give up two goals total.

"Now the reverse of the talk of you guys is on them now. We just got to kind of block all that out and stay with our game.

"Guys are feeling better about themselves and we got to ride this momentum into Carolina."

Rangers goal tender Igor Shesterkin stopped 30 shots but had his shutout bid spoiled by Teuvo Teravainen's third-period goal.

Earlier, goals to Frank Vatrano and Adam Fox earned the Rangers a 2-0 first-period lead, with Mika Zibanejad extending that advantage 16:48 into the second. Teravainen made it 3-1 before Copp rounded it out from Ryan Strome's assist 11:10 in the third period.

Rangers head coach Gerard Gallant was delighted with his team's display after a tight series, where the Hurricanes won Game 1 in over-time 2-1, before triumphing 2-0 in Game 2.

"Really, you look at the four games," Gallant said. "It's not just the two at home, but the four games have been pretty much one-goal games most of the way through.

"We are two teams that are close and battling. I just think it's been outstanding hockey by both teams."

The result means the Hurricanes are 0-5 on the road in the playoffs, while they are 6-0 at home ahead of Game 5 in Carolina.

Hurricanes coach Rod Brind'Amour said: "You've got to keep getting the chances. I'm happy that we're at least creating some offense.

"[Shesterkin] played well, you've got to give him tons of credit. But to me, the start is what did it to us."

Elsewhere, the Edmonton Oilers took a 3-1 lead in their second round series against the Calgary Flames, winning 5-3 in Game 4 after blowing a 3-0 first-period lead.

Nazem Kadri scored a decisive hat-trick for the Colorado Avalanche against the St. Louis Blues in Game 4, having been determined to perform after alleging threats and racist abuse.

Avalanche center Kadri was involved in a collision with Jordan Binnington in Game 3, bringing a premature end to the Blues goaltender's series.

Former NHL player Akim Aliu revealed on Twitter on Sunday he had subsequently spoken to Kadri, who he said had "been subject to so many racist attacks and threats since last night that police had to be brought in".

The Avalanche confirmed they were aware of threats made towards their player – a Muslim of Lebanese descent – and were working with local law enforcement to investigate.

In the meantime, Kadri responded on the ice with three goals in Monday's 6-3 win to put the Avalanche 3-1 up and on the brink of the Western Conference Finals.

"I wanted to come out tonight and really put a mark on this game, especially after what happened," Kadri said. "I tried to do that as best as possible.

"Sometimes you've got to be patient, and you've got to wait. I was able to strike early in the second period and was able to get the mojo going."

He added of the incidents: "People need to be aware this stuff still happens, and it's hurtful."

Speaking ahead of Game 4, Blues coach Craig Berube – who had questioned Kadri's role in Binnington's injury, referencing his "reputation" in an apparent nod to previous postseason suspensions – said of the threats: "I've got no comment on that stuff."

Tampa Bay Lightning goaltender Andrei Vasilevskiy added to his glittering resume as he shut-out the Florida Panthers 2-0 in Game 4 of their series, locking up a 4-0 series sweep.

It marks the sixth time Vasilevskiy has shut-out an opponent in a series-clinching win – the most in NHL history.

He also became the first player since at least 1955-56, when saves first started being tracked, to save at least 30 shots, allow no more than one goal, and earn the win in five consecutive games. 

The Lightning outscored the Panthers 13-3 for the series.

In Monday's game, Tampa Bay's home fans had to wait until the third period for the deadlock to finally be broken, as Pat Maroon got on the end of a Zach Bogosian assist, before Ondrej Palat sealed things with an empty-net goal with the clock winding down.

Speaking to post-game media, Lightning coach Jon Cooper highlighted how silly it was to question the quality of an all-time goaltender like Vasilevskiy after a tough start to their last series against the Toronto Maple Leafs.

"I’m not so sure there’s much more I can say about [Vasilevskiy]," he said. 

"It’s funny how the playoffs are – five games into the Toronto series and you’re asking all these questions about what’s wrong with Vasilevsky.

"It's never a doubt in our locker room. A goalie's job, if you want to be elite, is to give your team a chance to win.

"When a goaltender gives your team a chance to win, it comes in a variety of ways. Tonight, it was that he wasn’t letting anything in. And we’ve seen that time and time again."

Tampa Bay's Alex Killorn added that it is a joy to take the ice next to a future Hall-of-Famer.

"It’s pretty cool to play with a player that I think will go down as one of the best goalies that’s ever played the game," he said. 

"That’s how you kind of gauge players – how they perform in big-time games – and he’s been nothing but tremendous in his game."

Panthers interim coach Andrew Brunette said while it was a tough pill to swallow, it was a tremendous learning experience for his side after winning their first playoff series since 1996 to earn a shot at the reigning back-to-back Stanley Cup winners.

"They’re really good – I mean, they’re Stanley Cup champions for a reason," he said.

"Their evolution of how they were once a high-flying, kind of offensive team, and [now] they've found their recipe on how to win, and they stick with it.

"Obviously, we aspire to be them, and this was another learning experience for us. We need to be better."

New York Rangers coach Gerard Gallant assured his side can match the Carolina Hurricanes for physicality following a post-game scuffle, as the Rangers took a game back in their playoff series on Sunday.

As the buzzer sounded to end Game 3, a 3-1 win for the Rangers, Hurricanes forward Max Domi gave Rangers defenceman Ryan Lindgren a sudden cross-check.

The benches cleared and following the scuffle between the two teams on the ice, Gallant was also seen yelling at Hurricanes defenceman Tony DeAngelo, whose contract was bought out by the Rangers after a string of behavioural indiscretions.

While Hurricanes coach Rod Brind'Amour declined to comment on the issue post-match - citing that he did not see the shot from Domi - a visibly upset Gallant was more forthright, stating the Rangers are well-equipped to provide receipts.

“I wasn’t happy with the bulls..t at the end of the game that they initiated,” Gallant said. “We didn’t do that when the games were close. They put their guys out, that’s fine. They want to play like that, we've got guys who can match that.”

After two losses on the road, the Rangers bounced back with an important win as the series returned to New York.

Mika Zibanejad had a goal and an assist while Igor Shesterkin stopped 43 shots, for New York's second win in their past 10 against the Canes.

Message-sending is the norm in playoff series but after the post-game scuffle, Gallant made it clear his side will not be pushed around.

“I don’t like it at the end of the game,” he said. “The game’s over. We still got four games with these guys. We got the guy who can handle all their guys if we want to.

"We didn’t do it like that, but Domi took a cheap shot at our defenceman. You've got a long memory. You think about things, like I said, [the shoe] might be on the other foot someday.”

St. Louis Blues coach Craig Berube sent a veiled shot at Nazem Kadri, after the Colorado Avalanche defeated his team 5-2 to take Game 3 in their playoff series.

Kadri bowled over Blues starting goaltender Jordan Binnington less than seven minutes into the first period, forcing him to leave the game with a lower-body injury.

Binnington, who made three saves in as many attempts to that point, was replaced by Ville Husso, who stopped 19 of 23 shots.

Berube did not overtly blame Kadri for the collision following the defeat, but made reference to his notoriously frenetic and aggressive style.

"Look at Kadri's reputation," Beurbe said post-game. "That's all I've got to say.

"There are a lot of calls you can question. That's hockey. I'm not going to sit here and talk about calls, that weren't called or called, it's just not worth it.

"I can be disappointed but talking about it is not going to change it."

The Western Conference's first seed took a 2-1 series lead on the back of a Artturi Lehkonen brace and 29 saves from Darcy Kuemper.

Kadri, Logan O'Connor and Gabriel Landeskog also scored for the Avalanche, who bounced back from a 4-1 loss on their home ice on Thursday.

New York Rangers coach Gerard Gallant feels like there was not much more his side could do after falling down 2-0 in their series, losing both of the Carolina Hurricanes' home fixtures.

After leading until the final moments of Game 1, before the Hurricanes forced overtime and snuck away with a 2-1 win, it was another defensive struggle in Game 2, which suited the Hurricanes as they took it 2-0.

The breakthrough came from Brendan Smith in the second period, and that would be the only goal of the game until the Rangers pulled their goalie out of desperation in the final seconds.

Speaking to post-game media, Gallant said it was a true playoff hockey game, but despite only scoring one goal in two games, he feels his side played well once again.

"It was a good hockey game – low shots, a battle by both teams," he said. "It could've went either way again.

"It's tough – we came into this building earlier in the season twice and got dominated, [Carolina had] 50 shots I think.

"But we came in here, we played good defensive hockey, we battled hard. We only got one goal [across the two away games], that's the disappointing part of it, but we played a good hockey team, and played good hockey.

"We fell short a little bit – what are you going to do. Just get ready for the two home games coming up."

Gallant pushed back on the notion that his side is "disjointed" offensively, saying this is just what it looks like when the two best defensive teams in the league meet head-to-head.

"I wouldn't say [we are disjointed offensively] – I would say it's a case of two teams not giving up anything," he said.

"They're first in the league [defensively] and we're second in the league, but the disappointment is that we didn't take care of our power plays tonight. 

"Overall it's a top team, and it was a battle of a game. They're a good team – the best defensive team in the league.

"I'm happy with the way we've performed overall. I wish we would've got one of these two games – we probably could've – but that's the way it goes."

Goal-scorer Smith said everyone knows what kind of game it is going to be between these two sides, but he feels it favours Carolina.

“I think if we just stick to our style, it's eventually going to wear on teams and we're going to find a way to win,” he said.

The Tampa Bay Lightning's Ross Colton admittedly could not believe his eyes when he scored the winning goal against the Florida Panthers in a 2-1 victory, to take a 2-0 lead in their playoff series.

Colton was called onto the ice with under a minute remaining in the third period and the score locked at 1-1, but abandoned caution and made his way towards the net as Nikita Kucherov retrieved the puck.

Kucherov found Colton as he approached the net with an astonishing backhand, no-look flick off the boards as the Panthers defence converged onto him, leaving Colton with the relatively simple finish to win the game.

Colton's look of near-bewilderment almost said as much but he confirmed his awe at the 28-year-old Russian's assist afterwards.

“I couldn’t believe he [Kucherov] got it on my stick,” Colton said. “I think when we went in the corner, I just said, ‘Are you kidding me?’ like 10 times because I honestly couldn’t believe he put it on my stick.

"When you’re on the ice with Kuch, you’ve got to be ready for anything. He’s got eyes in the back of his head, because I don’t even know how he could tell I was there."

The Lightning were relentless defensively against one of the NHL's best attacking teams this season, snuffing out four Panthers power plays, including one with under five minutes remaining.

While singling out Kucherov as a "special, special player", Lightning coach Jon Cooper asserted the defensive performance and ability to snatch games in clutch moments was a reflection of the team's character.

“No, I’m not surprised,” Cooper said. “I’m just surprised they waited until 3.8 seconds left to do it.”

In Thursday's other result, the St. Louis Blues evened up their series with the Colorado Avalanche, winning 4-1.

The Carolina Hurricanes needed a late equaliser to send Game 1 of their playoff series against the New York Rangers to overtime, where they would score the golden goal to win 2-1 in front of their home fans.

Filip Chytil put the Rangers ahead in the first period with his goal from an Alexis Lafreniere assist as they tried to pinch Game 1 on the road.

Behind another stout goaltending performance from Rangers star Igor Shesterkin, the 1-0 scoreline would hold all the way through the second period and deep into the last, when Sebastian Aho finally found the equaliser with less than three minutes left on the clock.

After Carolina fans waited nearly an hour of game time for their first goal, they only had to wait three minutes into overtime to get their second, as Ian Cole landed an optimistic shot past Shesterkin the winner.

Just his second goal in 104 postseason games, Cole said shooting was not on his mind when he received the puck.

"I was looking to pass it to someone," he said. "No one was really kind of anywhere dangerous – so I was like, 'Well, I guess I'll throw it on net and see what happens'.

"Hockey's a game of weird bounces, and it happened to go in. Not the prettiest, but we'll take it."

Hurricanes coach Rod Brind'Amour was proud of his side pulling through the way they did, but he acknowledged it felt like they got out of jail.

"Kudos to our guys, they got it going in – it certainly was a good third period," he said.

"[But] we're not going to get away with that. Not playing two periods and expect to win a game — especially at this time of year against that team.”

Rangers coach Gerard Gallant felt his team did not get the reward for their play, going as far as saying their first two periods were as good as they had played all season.

"They put a big push on in the third period in the first 10 minutes, and we weathered that storm," he said.

"But the first two periods was perfect hockey for us... I thought it was our best game of the year, I really did."

Game 2 will remain in Carolina on Friday before heading to Madison Square Garden in New York for Game 3 and Game 4.

Goaltender Andrei Vasilevskiy was the hero as the Tampa Bay Lightning boosted their three-peat bid by winning 4-1 over the Florida Panthers in Game 1 in second round of the Stanley Cup playoffs.

The Lightning beat the Panthers in the first round of last year's playoffs 4-2 after going 2-0 up in the series and Tuesday's win got them halfway there in this year's Eastern Conference semi-finals.

Tampa Bay coach Jon Cooper was full of praise for 27-year-old Vasilevskiy, who made 34 saves as the Lightning fired in three third-period goals to get the win.

Vasilevskiy's 34 saves are the most he has had in a game this postseason, while he has stopped 94 of 99 shots over the past three games.

"Look at the saves he makes at the times we need them," said Cooper in his 124th playoff game with the Lightning.

"To me, that's what great goaltenders do and they give you a chance to win a hockey game and that’s what our guy did again tonight."

Nikita Kucherov, who scored a goal and had an assist, also hailed the Russian goaltender.

"He brings 100 per cent effort every single game and everybody's just trying to take his energy and bring it to your game," Kucherov said.

"He's a leader ... he's our best player."

Florida had taken the lead through Anthony Duclair in the first period but the Lightning hit back with four unanswered goals from Corey Perry, Pierre-Edouard Bellemare, Kucherov and Ross Colton to take the win.

"We're still learning and unfortunately we had to learn again tonight. We will be better next game," Florida interim coach Andrew Brunette said.

"They are too good of a team, a veteran team, and they're not going to open the door for you. We had our opportunities. On to the next game."

The Vegas Golden Knights have fired head coach Pete DeBoer.

DeBoer's exit was announced on Monday and comes after the Golden Knights failed to make the playoffs for the first time in their brief history.

He replaced Gerard Gallant in January 2020 and led the Golden Knights to the Western Conference Finals, where they lost to the Dallas Stars in five games.

They progressed to the Stanley Cup semi-finals the following season, losing in six games to the Montreal Canadiens, but a 43-31-8 record in 2021-22 meant the Golden Knights missed the playoffs having reached the postseason in each of their first four campaigns after joining the NHL in 2017. 

"We would like to thank Pete DeBoer for his commitment to the Vegas Golden Knights over the past three seasons," said Vegas Golden Knights General Manager Kelly McCrimmon.

"Since joining the organisation, Pete and his staff have guided us through some of the most unique and challenging circumstances we've witnessed since our franchise entered the NHL.

"After lengthy discussions over the last two weeks, we believe that a new coach will put us in the best position to succeed next season."

DeBoer had a 98-50-12 record with the Golden Knights in the regular season.

Star winger Artemi Panarin proved the difference in Game 7 for the New York Rangers, with his goal in overtime clinching a 4-3 win and the series on Sunday.

Overtime seemed fitting for what has been such a tight series, and the 30-year-old Russian put the Rangers up in rare circumstances, shooting through a wall of Penguins players in a power-play to score.

It was the third-straight come-from-behind victory in the series for New York, who tied the game with 5:45 left in regulation via Mika Zibanejad.

Rangers coach Gerard Gallant felt the conditions did not suit Panarin but he had the requisite skill to save his side when it mattered most.

"He's the guy, when it gets to overtime, I said to myself that he was going to score," Gallant said after the win. "If we get the winning goal, it's going to be him. Sure enough, he makes a great play.

"You know what? Honestly, the ice wasn't great tonight. The puck was bouncing and it affects his game more than the other guys. People get frustrated at times. I think we saw a little of that.

"I just thought he wasn't having his best night. He tried hard, he competed and got some pucks out. He usually makes a lot of plays and tonight it just wasn't there, but you just get a feeling with a guy like him that he can do that for you. And that's what he does."

The Penguins were bolstered by the return of Sidney Crosby after he missed Game 6 with an upper-body injury, caused by a hit from Jacob Trouba. The visitors equalised on a power-play following a penalty for high-sticking from Trouba and though they hit the lead, could not manage to see the series out.

In Sunday's other result, Johnny Gaudreau's goal in overtime secured the series for the Calgary Flames against the Dallas Stars, moving to the second round with a 3-2 win.