The Boston Celtics' utterly disappointing 2019-20 season has finally come to an end, with a hugely impactful summer looming.

These are three predictions for how one of the most significant offseasons in Celtics history will play out.

3. Kyrie Irving opts out, bails in free agency

Kyrie Irving
CP

Though he's said nothing concrete to suggest he's leaving the Celtics this summer, Irving's performance in his team's final game of the season indicated almost more than any such words could.

He shot a dismal 8-of-22 against the Milwaukee Bucks in Game 5, throwing up several hopeless contested two-pointers and even an air ball from three-point range multiple feet wide of the rim, and made the same confounding defensive decisions that began rearing their ugly head two games earlier.

Remember LeBron James' much-maligned performance in Game 6 of the 2010 Eastern Conference Semifinals, the final game of his first stint with the Cleveland Cavaliers? If his attitude and overall wherewithal indicated an imminent departure from his incumbent team come free agency, like so many insisted, Irving's vexing play in Game 5 did exactly the same, but to an even more convincing extent.

Of course, his post-game comments, while typically opaque, definitely didn't spell optimism for Boston's hopes of retaining him, either.

“Truth be told, it’s no time to be disappointed. You take your lessons, you take your ass-whipping that they handed us, and you move on,” Irving said, per Chris Forsberg of NBC Sports.  “It’s a basketball journey… It was a great opponent for me to play against for the rest of my career because I know I won’t forget something like this, and the taste of defeat in this type of style, being down 1-4, I haven’t felt. For me, it’s just moving on to the next thing, and just seeing where that ends up.”

Expect Irving to opt out of the final year of his contract leading up to July 1st, with rumors growing louder by the day that he'll be signing elsewhere in free agency.

Whether he ends up with the New York Knicks or another big-market team with ample cap space, it will ultimately be best for not just Irving, but the Celtics, too.

2. Al Horford opts out, re-signs on multi-year deal

Al Horford, Celtics

Irving was never his team's most valuable player during his two-season stint in Boston. That honor goes to Horford, who bounced back from a lackluster start to the 2018-19 season, the result of nagging pain in his left, to re-establish himself as perhaps the league's most versatile big man over the final weeks of the regular season and the playoffs.

Horford has a $30.1 million player option on the four-year, $113 million contract he signed with the Celtics in the summer of 2016. He turns 33 in June, an age at which it's fair to expect most players' impact to begin declining due to a combination of waning athleticism and general wear and tear.

But Horford showed no signs of slowing down when healthy and rested this season, and the importance of understanding and intellect to his overall on-court influence means he should be better suited to mitigating the effects of Father Time than most. A smart team will continue limiting his minutes and games played during the regular season, only asking him to shoulder the heavy two-way burden he's fully capable of carrying when it matters most.

Horford, to put it simply, is just a perfect fit for what Brad Stevens' Celtics do both on the floor and in the locker room. He knows that better than anyone, and should act accordingly by securing his financial future with a new contract that's three to four years in length and pays him around $25 million annually.

Horford has been one of the league's most underappreciated players throughout his stellar career.

By staying in Boston going forward and potentially finishing his playing days in green, Horford has the opportunity to cement himself as a franchise pillar, helping keep the Celtics afloat in the Eastern Conference when many will have counted them out.

1. Contract extension talks for Jaylen Brown end early

Jaylen Brown
CP

Brown was one of the only even somewhat bright spots for Boston in a season marred by a lack of chemistry and cohesion both on and off the floor.

After getting off to a horrible start and being moved to the bench in favor of Marcus Smart, the third-year wing quietly averaged just below 20 points per-36 minutes with an encouraging true shooting percentage of 57.5.

At 22, Brown still has the makings of an immensely valuable player, the type who can play multiple roles on each side of the ball in both the regular season and playoffs. But there's variance to the trajectory of his career from here, and Danny Ainge, never afraid to drive a hard bargain, knows it.

Brown will want the max, and rightfully so, while the Celtics would be best served by making him prove he's worth that price in 2019-20, then willingly giving it to him in restricted free agency the following July.

Boston will probably be in a state of transition next season, when maintaining long-term flexibility will be of nearly as much importance as winning games.

All of those factors and more add up to both player and team understanding that Brown's future with the Celtics will be most prudently decided next summer.