The Boston Bruins are about to enter their 71st playoffs in their storied franchise since 1924. In only six of those years did the Black and Gold reach the pinnacle of any NHL season — hoisting the Stanley Cup. In the last three seasons, the franchise has played a total of six playoff games and begins this postseason with a coach completing his first full 82-game regular season.

Regardless, hope springs eternal with high expectations for a seventh Cup to culminate the 2017-18 campaign. However, too many significantly new variables enter the scene any year with regard to must-do items to give the best chance for a deep run each spring.

For the Bruins to play deep into this June, here’s a look at five musts in order of priority for them to get the momentum rolling against the Toronto Maple Leafs in Round 1 that begins Thursday night at TD Garden.

Score first

One of Bruce Cassidy’s unfortunate phrases both during the season and in the last five games with the Bruins giving up the first goal is: “chasing the game.” As in Sunday’s faltering finale for the Eastern Conference regular-season crown when he said, twice, “The third [period] we started playing together, but then it’s too late; we’re chasing the game. We’ve got to find a way to get out in front early. Not early – we’ve got to find a way to not continually chase the hockey game.”

The Bruins chased many a game this season, falling behind early. They proved resilient with many a comeback among their 50 total wins.

Any number of NHL analytics websites, however, validate that the team that scores first some 67 percent of the time, wins the game. Apply that stat to a 7-game series and it’s crucial that the Black-and-Gold score first more often than not.

Chasing a playoff game is even more challenging than the regular season with lockdown defense the order of the day when a team gets the lead.

The kids need to be steady and playoff ready

The rebuilding of the team this season with more rookies than any in recent memory was more successful than anyone remotely envisioned. Again, the playoffs are a different animal.

Aside from Anders Bjork not making it to the postseason, Charlie McAvoy, Danton Heinen, Jake DeBrusk, Matt Grzelcyk and Ryan Donato will be front and center for Boston to advance. McAvoy proved last spring he is a top-2 defenseman for years to come. The latter four need to follow McAvoy and prove they can handle the physicality of the playoffs from the outset – and contribute to each game.

“We have some younger guys,” Cassidy said Sunday about the Toronto matchup, “we have some (veteran) guys we’re going to lean on.” He could have included all in the same sentiment. Cassidy will lean on the youth.

The Rask task: dominate

The first two months of the season were not vintage Tuukka Rask. The next three months, he was the best goaltender in the NHL before morphing back to subpar performances in the final month.

The playoffs are all about goaltending first. As Rask goes, so very likely go the Bruins. The March and April schedule was a killer and this week’s rest is the most important requirement for the Black and Gold.

“Taking a breather tomorrow,” Rask said Sunday night, “and then back to work. Intensity and physicality goes up obviously [in the playoffs]. Every play kind of matters and mistakes play a big role. If you make a mistake, most likely you’re going to pay for it.”

That starts from 24 square feet out.

Match Toronto with quicker sticks and 60-minute intensity

“They’re one of the toughest teams that I think we’ve played against all year,” Brad Marchand said about the Leafs, “and it will be a good battle.”

“It should be a terrific series if both teams are on their game,” Cassidy added, “and that’s playoff hockey right there, a lot of speed, probably a lot of physicality.”

The Leafs beat Boston in three of the four regular-season encounters. They match up well, especially up front with a comparable blend of veteran and youth, and with Frederik Andersen in goal. They added a playoff-savvy Patrick Marleau in the off-season and several veterans are entering free agency this summer, using their playoff performance for a bigger payday. They will dress 10 players who played 80 or more games and 10 with 40 or more points. Mike Babcock is arguably the best coach in the NHL.

Bruins need a major Nash contribution

Most puck pundits knew Sweeney was all-in for a long playoff run when he traded the store in Ryan Spooner, Matt Beleskey, Ryan Lindgren and a first-round draft pick for Rick Nash. So far that’s been a bust to put it mildly. With the season-ending injury to Brandon Carlo, Nick Holden has panned out as Sweeney’s best move during the stretch run and into the playoffs.

The Bruins’ first line of Marchand, Patrice Bergeron and David Pastrnak can’t — and won’t — carry the team in the playoffs. The second line needs Nash on the right wing to keep the third and fourth lines intact, not to mention the need to also keep intact the four centers in Bergeron, David Krejci, Riley Nash and Noel Acciari.

Nash is in the final year of a $62.4 million contract; $8.2 million this season. He has always been a scorer; being called a “gamer” is yet to be applied.

“Hopefully they’ll all be available,” Sweeney said Monday about injured players availability and without referencing Nash who has been on concussion protocol and has not played since March 19.

He was then pressed about the Nash status.

“He was on the ice today,” Sweeney added. “Yup.”

Not clear if he meant yup, he was on the ice – or yup, he’s playing Thursday.

Pretty clear about one thing: Yup, the Bruins need Rick Nash, the scorer and the gamer, ready for Game 1 and well beyond.