2020-21 will go down as the season the Blackhawks turned the page from old core to new core

The 2019-20 Blackhawks, while far removed in terms of success, still were built around the remaining framework of the 2015 Stanley Cup team.

The 2021 Hawks, while winning games more like the 2015 team, are not.

So when hockey historians and fans look back on the Hawks’ most recent dynasty era, the would-have-been season of 2020-21 — starting in October and running through April — will be remembered as the time the page turned on the Hawks’ old core.

Defenseman Brent Seabrook’s retirement Friday, 15 months after what turned out to be his final game, cemented that even further.

In October, wing Brandon Saad was traded to the Avalanche and goalie Corey Crawford’s contract wasn’t renewed. In December, captain Jonathan Toews began his leave of absence, which looks increasingly likely to last for the duration of the 2021 season and perhaps longer.

In January, Crawford abandoned his short-lived stint with the Devils and retired. In February, forward Andrew Shaw suffered yet another concussion, putting his career in doubt. And so far in March, Seabrook and Shaw have been moved to long-term injured reserve.

General manager Stan Bowman gave a less-than-optimistic update on Shaw’s status Friday.

‘‘First and foremost, I’m just concerned about him to make sure he gets himself in a better place,’’ Bowman said. ‘‘When he feels better, we’ll have a better feeling if he’s going to be returning to play or not. That’ll come from him and the doctors.’’

But Bowman also reflected on the Hawks’ old core aging — or ‘‘injuring’’ — out, just in time for the youth to move in.

‘‘I was thinking of that [Thursday],’’ he said. ‘‘The number of guys that were here, it’s dwindling. . . . I guess it shows time’s passing and we’re all getting a little bit older. But it was a pretty special ride with that group that was with us for a long time.’’

Wing Patrick Kane and defenseman Duncan Keith remain the two championship-era pillars still going strong. At 32, Kane seems to have improved with age and might win his second Hart Trophy this season. Keith, 37, appears to have at least another season or two left in him, too.

Nonetheless, the Hawks have gone from seven 2015 holdovers last season to two playing presently.

And while Teuvo Teravainen, Niklas Hjalmarsson, Antti Raanta and Saad remain good players on other teams, even more members of the 2015 bunch — Marian Hossa, Patrick Sharp, Johnny Oduya, Kris Versteeg — had retired even before the last six months.

‘‘It’s strange; it is,’’ Bowman said. ‘‘Those players have been fixtures for a long time, and they’ve brought us some tremendous memories. That’s something that can’t be taken away, and we’ll always be tied together for those great years as a group.’’

But these Hawks aren’t those Hawks anymore. These Hawks are turning out to be pretty good, however. And if the Hawks hope to enter another championship era soon, this clearly was the right way to go.

Equating the Hawks’ ‘‘new core’’ of Alex DeBrincat, Kirby Dach, Ian Mitchell, Adam Boqvist and Kevin Lankinen, surrounded by important role players such as Dominik Kubalik, Dylan Strome, Philipp Kurashev, Brandon Hagel and Nicolas Beaudin, to the early days of the Toews-Kane-Keith-Seabrook-Crawford era might be slightly premature.

But the comparisons are apparent. As the chapter fully turns from one to the other in 2021, even the old guys see the Hawks’ future coming into focus.

‘‘Throughout the lineup, everyone’s pulling on that rope,’’ Seabrook said. ‘‘The last couple of years, it’s been tough around here. And this team is having fun. They’re enjoying it, they’re in every game and they’re competing.’’