The Boston Red Sox will begin spring training with several newcomers, including outfielder Franchy Cordero, as the team rebuilds its roster after a last-place finish in the American League East in 2020. AP Photo/Charles Rex Arbogast

Every great team begins somewhere. It’s rare indeed that a team is thrown together in a single offseason and achieves greatness. It takes time to find the right pieces and implement a plan that allows those players to reach their potential as champions.

All of this leads to the main question surrounding the 2021 Boston Red Sox: Is this the beginning of a long, painful rebuild that will reap rewards several years from now, or is that process well underway?

We’ll see the early answers later this week in Fort Myers, Florida, when Red Sox pitchers and catchers report for duty.

The Red Sox believe they will be much better this season. They think they have quietly assembled a group of experienced veterans who will immediately change the attitude in the Fenway Park clubhouse. They think this could be a team similar to 2013, when fans were underwhelmed by the additions of Jonny Gomes and Shane Victorino and Ryan Dempster, but were later astonished when that team won the World Series.

No one is suggesting the 2021 Red Sox will be champs. But could they be improved enough to make it to the postseason? That would certainly be a step in the right direction.

We’ve seen this before. The 2013 Red Sox were an example of smaller moves paying off. There were plenty of years things didn’t go as well. In 2015, general manager Ben Cherington brought in Rick Porcello and Wade Miley to stabilize the starting rotation. Pablo Sandoval was a big-name signing and would take over third base. Surely Boston fans would adore the Panda, a three-time champion with the Giants.

Those moves backfired, and the Sox finished last for the second straight year.

Boston Bruins’ Chris Wagner (14), second from right, celebrates his short-handed goal against the New York Rangers with Jeremy Lauzon (55), Charlie Coyle (13) and Kevan Miller (86) during the second period of an NHL hockey game Wednesday, Feb. 10, 2021, in New York. Bruce Bennett/Pool Photo via AP

The summer of 2015 was also a dark one for the Boston Bruins, coming off a fifth-place finish and failing to qualify for the playoffs. Just two years removed from an appearance in the Stanley Cup finals, and four years from a championship, newly named general manager Don Sweeney faced pressure to make a big splash and reinvigorate the roster.

Instead, Sweeney played the long game. He traded away 2011 hero Milan Lucic to the Kings. Then he sent Dougie Hamilton, a young defensive cornerstone, to Calgary. Bruins fans were dizzied by the names and draft picks coming in return. Four days later, goalie Martin Jones — acquired in the Lucic deal — was sent to San Jose for another pick and a prospect.

As the dust settled, there was even more pressure on Sweeney to do something with all of this young talent. Get an established defensemen. Move up in the draft.

Sweeney stayed the course. The Bruins were marginally better that following year. They were back in the playoffs a season later. They were in the Stanley Cup finals two years after that.

Not all the names in those deals worked out. Colin Miller spent two seasons with the Bruins and made little impact. Jakob Forsbacka Karlsson is back in Sweden. The jury is still out on Zach Senyshyn.

But Jeremy Lauzon and Jakub Zboril make up a third of the Bruins’ outstanding defensive corps this year, each playing in all 14  games this season. Sean Kuraly and Trent Frederic also have played in all 14 games. The Bruins sit atop the new East Division and have shown signs of another deep postseason run.

You could easily make the comparison between Lucic and Andrew Benintendi. The popular left fielder was traded to the Kansas City Royals last week. In return the Red Sox got Franchy Cordero and four minor league prospects (three to be named later).

Adam Ottavino might be the baseball equivalent of Miller, an effective piece of the current roster who is gone by the time the prospects blossom into stars.

More than anything, the most obvious comparison is between Bloom and Sweeney. Two Ivy-educated leaders who believe they can make their team a little better each year … and ultimately be a powerhouse year after year.

There is little patience here in the Golden Era of Boston Sports, but Bruins fans feel pretty good about their team right now. As the boys of summer take the field this week in Florida, it’s a good reminder that Boston’s hockey team followed a similar path to get to where it is today.

Lewiston native Tom Caron is a studio host for Red Sox broadcasts on NESN.