BOSTON — Kyrie Irving turned the NBA world upside down multiple times this summer.

It happened the first time after news leaked out that he had asked the Cleveland Cavaliers front office to trade him from the team he helped lead to a championship in 2016.

Then Irving was in the spotlight again as the centerpiece of a league-shaking trade that sent him to the rival Boston Celtics in exchange for a package that included Isaiah Thomas and Jae Crowder.

Now detached from the partnership he created with LeBron James, Irving enters the 2017-18 season as one jewel of the Celtics’ offseason overhaul, along with Gordon Hayward, who signed as a free agent.

Only four players remain from Boston’s roster from a year ago, when it outfought Cleveland for the East’s top seed, only to fall to the Cavs in five games in the Eastern Conference finals.

Along with Al Horford, the Celtics have a brand new “Big Three” as they continue their pursuit of the Cavs. While Irving maintains his departure from Cleveland wasn’t about James, he now has exactly what he says he wanted: the leadership role in building a championship team.

Still, he downplayed the idea that this season is more important than any other during his six-year career.

“Every moment in my life is pretty important,” Irving said. “I wouldn’t say that it’s the most important. I would say it’s probably the most interesting.”

Here are some things to watch for with the Celtics this season:

EARLY REMATCH

One of the byproducts of the deal that brought in Irving was that president of basketball operations Danny Ainge had to part with Thomas, who had become not only a two-time All-Star, but the team’s emotional leader as well.

A hip injury he suffered in the playoffs won’t allow Thomas to be on the floor when his new Cavaliers team hosts the Celtics in both team’s season opener on Oct. 17.

But it will make for an interesting on-court reunion for Irving and James.

REUNITED

When Hayward entered free agency, Boston was thought to be high on the list to land him because of his previous association with coach Brad Stevens.

Stevens was Hayward’s college coach at Butler, and the pair came within a missed last-second shot by Hayward of winning a national championship.

While Hayward said the ultimate decision to leave Utah for Boston was basketball-driven, he said the connection he had with Stevens was a factor.

“I always had a dream to play in the NBA, but he was the first person to tell me that I could get there some day,” Hayward said.

After growing into a first-time All-Star with the Jazz, he now will have the chance to play a key role again in a “position-less” system that promises to utilize Hayward’s skills as a scorer and passer.

TRIMMER SMART

Guard Marcus Smart will look a little different on the court this season after shedding 20 pounds in the offseason.

He said he struggled with back pain during the latter part of last season at 240 pounds and made it a priority to change his diet and slim down.

One thing that won’t change, Smart said, is how he plays the game. His physique has changed, along with many of the players around him. But the goals are the same, even has he prepares to take on a new role as one the Celtics’ veterans. Smart, Horford, Terry Rozier and Jaylen Brown are the only returning players from last year’s roster.

“Marcus is a critical part of our team,” Stevens said. “I think ultimately we want our identity to be a team that gets better every day. And I think his mindset, his competitive spirit, his toughness, his will — all of those things make teams better.”


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