Boston Celtics fans had two weeks to brace themselves for Al Horford’s departure and yet that didn’t make it any easier when, three hours after the start of free agency on Sunday night, word arrived that Horford was signing with the rival Philadelphia 76ers.

It was a stomach punch, one amplified by rampant speculation on Sunday that Boston might just be the mystery team planning to splurge for Horford’s services. They weren’t and, frankly, it was hard to ever envision a path to that being a reality. Once Jimmy Butler got dealt to Miami in a sign-and-trade, the Sixers were able to jump out and yell, “surprise!” 

On the same day that most Celtics fans simply muttered, "good riddance," to news that All-Star point guard Kyrie Irving was signing in Brooklyn, joining forces with Kevin Durant in the process, it was The Process that broke Boston’s heart. Philadelphia’s free agency started quietly with J.J. Redick taking his talents to New Orleans but the Sixers, quiet at the onset of the chaos, soon completed a flurry of moves including signing Tobias Harris to a five-year, max contract extension.

The idea of Horford in red, white, and blue will leave Celtics fans nauseous. For the past three seasons, Horford has been Boston’s secret weapon against Joel Embiid — amongst others, including league MVP Giannis Antetokounmpo — and Horford might have been the biggest reason that Boston dispatched the Sixers in five games in the 2018 East semifinals.


Now, Horford will share a frontcourt with Embiid, forming one of the more formidable big-man tandems. All this as the Celtics, a measly $4.8 million room midlevel exception dangling from their pockets, are left hunting the bargain bin for a serviceable big given the departures of Horford, Aron Baynes, and Marcus Morris.

Here’s why Horford’s departure really stings: Three years ago, Horford squashed the stigma that free agents didn’t want to play in Boston. The Celtics were a bunch of gritty overachievers before Horford arrived — heck, his Hawks had bounced Boston in six games in Round 1 of the 2016 playoffs — and the Celtics morphed into legitimate contenders with him (making it to the East finals in both 2017 and 2018).

Now, Horford is gone. Few will begrudge him for seeking one last major payday. Horford turned 33 last month and, despite $161 million in career earnings, including a $28.9 million payday last season, he battled knee issues throughout the 2018-19 season and the team managed his playing time early to ensure he was upright in the postseason. Still, even if the money was part of the motivation, Horford’s exit seemed more like a sign that he saw more potential in what Philadelphia was building than with Boston’s current makeover.

The Celtics’ path to sustained contention runs directly through the Sixers, who might just be the early favorite in the East (at least until Kawhi Leonard makes a decision about his future, or Durant gets healthy again in 2020).

The Celtics’ new-look frontcourt? That’s a bit of a sore subject. The team formally came to an agreement with Walker on a four-year, $141 million contract on Sunday but — even as the Celtics and Hornets eyed a sign-and-trade that will deliver Terry Rozier to Charlotte — there are still gaping holes in Boston’s big-man depth chart and very few means to immediately patch them.

Boston is left to see what that $4.8 million midlevel can fetch. The Celtics might simply elect to give youngsters like 2018 first-round pick Robert Williams, 2019 first-round pick Grant Williams, and 2017 second-round pick Semi Ojeleye some available minutes and evaluate the big-man spot further down the road if no one sways them before then.

Ultimately, Boston’s success next season almost certainly hinges on the development of the team’s youngest players, especially the tandem of Jaylen Brown and Jayson Tatum. If those two make leaps and a healthier Gordon Hayward finds his old form, the Celtics might just stay in the mix in the East.

Just don’t ask who will defend Horford in a playoff series. Maybe now the Celtics fans who often downplayed Horford’s contributions will see just how important he was to the team’s overall play. Horford’s stat line will never leap off the page but he impacted winning in so many different ways. Boston’s on/off splits with Horford remain a staggering indication of just how much he tends to make good things happen.


Celtics fans had five months to brace for Irving’s departure. Back in early February he barked, “Ask me July 1,” to questions about his future and brooded in the aftermath. By June 30, he had his new home.

Some will suggest that Irving’s time here was a failure. Undoubtedly, the Celtics never played to their potential with him. But the cost to land Irving wasn’t prohibitive — even if trading the likes of Isaiah Thomas and Jae Crowder stung initially — and Boston didn’t handcuff itself from future moves by landing Irving.

Still, Irving caused unnecessary tension in Boston’s locker room with his ever-changing mood and repeated criticism of the team’s youngest players. Was he to blame for the 2018-19 Celtics going completely off the rails? Of course not. But, as the leader of that team, their failures ultimately fall back on him.

Walker’s arrival should help Celtics fans move on from Irving. Boston is going from one All-Star point guard to another. But there are less concrete options in the frontcourt. And that makes Horford’s departure that much tougher.

Celtics fans will miss Horford’s quiet leadership. They’ll miss his free-throw flinches. They’ll miss all the little things he did that went unnoticed.

But the pain many Celtics fans are feeling amid Horford’s departure suggests that, maybe most fans actually did notice everything Horford did, and understand how hard it will be to replace them.

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