The Boston Celtics season ended far sooner than they were hoping and another postseason disappointment may be setting up an offseason of big changes.

As the Miami Heat knocked off the Milwaukee Bucks and New York Knicks, it appeared a path was opening for the Celtics to return to the NBA Finals and finish what they started last year. But it turns out, like New York and Milwaukee before them, they didn't have any answers for Jimmy Butler or the Heat either.

Jayson Tatum and Jaylen Brown both struggled at times during the postseason. And what looked like the best-supporting cast of this Celtics era had their weaknesses exposed and went cold at the worst possible times. Boston could run things back with the same core and hope for a better result, but they made also need to consider some serious roster changes this summer.

Celtics who won't be back next season: 3. Mike Muscala

Muscala was picked up at the trade deadline for Justin Jackson and a pair of second-round picks. With his size and shooting touch, he looked like a nice deep-bench addition for Boston. He did play well over the rest of the regular season, hitting 38.5 percent of his 3s in 20 games.

However, there wasn't really a meaningful role to be had in the playoffs for Muscala, as the interior defense of Robert Williams and Al Horford proved to be much more valuable. At 31 and as an unrestricted free agent, Muscala will likely be looking for a spot where he can maximize his playing time, even if it's still just as a floor-spacing big toward the end of the rotation. Boston may try to bring him back, but they'll have other more pressing priorities and Muscala will likely find more minutes elsewhere.

Celtics who won't be back next season: 2. Blake Griffin

Blake Griffin settled into a comfortable role with the Celtics after signing a one-year deal last offseason. He only appeared in 41 games but his 3-point shooting numbers bounced back a bit (34.8 percent), he finished around the rim and added some value as a distributor from the elbows. However, like Muscala, he completely disappeared from the playoff rotation.

Griffin is just 33 and still very skilled, he can contribute on a winning team as a lightly used bench player. But the Celtics may prefer someone who is healthier and more available, presenting a more consistent alternative to Horford and Williams. With Danilo Gallinari (hopefully) healthy and likely to pick up his player option for next season, Griffin's role will be filled and his roster spot perhaps used on a player with more athletic upside (imagine reading that sentence about Griffin seven or eight years ago).

Celtics who won't be back next season: 1. Joe Mazzulla

This one is hard because, for much of this season, Mazzulla seemed to be a big success. Young and relatively inexperienced, he stepped into an incredibly difficult situation — interim coach, replacing Ime Udoka, a popular, locker-room-uniter who had led this team to the NBA Finals last season before earning a season-long suspension for an inappropriate sexual relationship with a subordinate.

Mazzulla helped elevate the Celtics' offense, leading them to the No. 2 seed in the East, a better record than last season and earning himself the permanent job and a multi-year contract along the way. But the way the Celtics collapsed against the Heat — looking listless, uninspired and with no meaningful tactical adjustments through the first three games of the series put him right on the hot seat. After Game 3, reports leaked that his job could be on the line and ESPN's Adrian Wojnarowski shared additional details about a rift that never healed.

The Celtics battled back and nearly pulled off a historic feat, becoming the first team in NBA postseason history to come back from a 3-0 deficit.

But they didn't.

And, honestly, the way that it ended may only underscore how problematic it was that they were in this hole in the first place. They needed a miraculous Derrick White putback to win Game 6. And they found themselves in a double-digit hole before the end of the first half of Game 7 at home. Mazzulla didn't really solve the Heat or make any tactical maneuvers that saved the series. The Celtics simply won when they made shots and lost when they didn't. That's well and good if you're an underdog or in a series where you are evenly matched. But on paper, the Celtics had every advantage and should never have been in a position against the Heat where shooting variance alone was enough to send them home.

Rightly or wrongly, that's going to come back on Mazzulla and could bring his Celtics' tenure to a premature end.

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