Las Vegas — Bruce Cassidy didn’t think his job was in jeopardy, having taken Boston to the NHL playoffs all six seasons as coach and serving in the Bruins' system for 14 years.

When he was fired on June 6, Cassidy was shocked and upset ... for a few hours. The Vegas Golden Knights quickly jumped in, reaching a deal a little more than a week later to hire Cassidy.

“You don't have a lot of time to sort of mourn because you're on to preparation for the next team,” Cassidy said.

The Golden Knights entered Thursday with the chance to win the Pacific Division and claim the Western Conference's top seed. Vegas already had tied the franchise record with 109 points.

Back in Boston, the coach who replaced Cassidy, Jim Montgomery, has had an even better season. The Bruins set an NHL record Sunday night by winning its 63rd game and another mark Tuesday night by reaching 133 points.

And the coach Cassidy replaced in Vegas, Pete DeBoer, is experiencing great success in Dallas. The Stars led the Central Division with 106 points through Wednesday, a point ahead defending Stanley Cup champion Colorado.

DeBoer took over for Rick Bowness, who went to Winnipeg and took the Jets to the final Western Conference playoff spot.

Got all that?

“I think it shows you the level of coaching at the NHL,” DeBoer said. “Situations are different, personnel is different on different teams, but the top coaches that work in this league are all very good at what they do. That’s why you see guys being able to move around and have success.”

Tenures are short in the NHL: Of the league's 32 coaches, 23 were hired since 2000.

By that measure, Cassidy had a long run with the Bruins, and the organization didn't rush to let him go. Cassidy, who took the Bruins to Game 7 of the 2019 Stanley Cup Final, was let go three weeks after Boston's first-round playoff loss to Carolina and replaced him nearly a month later.

“The standard here is unreal,” Montgomery said of Boston. “Just grateful to be part of it.”

The standard also is high in Vegas, even though that franchise is just in its sixth season. The Knights went to the Stanley Cup Final in their first season and are looking for their third division title.

The Golden Knights' management has shown a willingness to quickly move off coaches, with Gerard Gallant getting fired in the middle of his third season and DeBoer getting the hook when Vegas missed the playoffs for the first time last season.

“Ultimately, a manager does what he believes is in the best interest of his organization, so that was the reason that we made the decision that we made with with Pete," Vegas general manager Kelly McCrimmon said. “That’s the reason that Boston made the decision that they made. ... You’re always evaluating where where you’re at, where you’re going and what you want to look like trying to get there.”

Cassidy knew the expectations when he took the Vegas job — that the team enters each season hoping to win the cup — and though he spoke with other clubs, he preferred that high-pressure situation over a rebuilding project.

That still didn't make it easy to leave Boston. Going back to his days as the head and assistant coach for Providence in the American Hockey League, Cassidy and his family called New England home for 14 years. They still own a home in Cape Cod, Massachusetts, that they'll return to in the summer, and their two middle-school-aged children were born in the area and had to adjust to living across the country.

Turns out, he said “they love it here.”

“They're resilient. ... They have lot of friends, so there’s been no emotional stretches where we’ve had to really keep an eye on them, just normal middle school sort of issues. Some of their friends from Boston have visited because people like to come to Vegas, so if it was Winnipeg, it might've been harder,” Cassidy said with a laugh.

But there is no joke about the job he has done this season, not that it's been easy.

The Knights have started a franchise-record five goalies, and there are still questions about who will be in the net during the playoffs. Mark Stone, Jack Eichel, Shea Theodore, Alex Pietrangelo and Zach Whitecloud have missed extended time for health and personal reasons.

“Bruce and his staff have done a great job at managing lineups that were really depleted for long stretches of time,” McCrimmon said. “I think that where you’ve seen them have a real positive impact is how well some of the players have played that have been called up from Henderson or that took on bigger responsibilities within our team.”

Cassidy, Montgomery, DeBoer and Bowness are veterans, though, and they've learned how to adapt over the years.

“As a coach, you grow in confidence and conviction in what you’re doing,” DeBoer said. “With that, I think your message becomes clearer and better. There’s no doubt as you take this journey, every stop you’re a better coach. I don’t know at what point it clicked in.

"Looking back, I came into Florida as the youngest coach in the league. I was 40 years old. I can’t believe it’s 15, 16 years later. It feels like yesterday.”