Celtics Insider Reveals How Boston Could Have Kept Al Horford

The 2025-26 Boston Celtics have totally revamped their starting center rotation, although as of this writing it appears head coach Joe Mazzulla is looking to suss out the exact hierarchy through training camp and the preseason.

All three of Boston's rotation centers — starter Kristaps Porzingis and reserves Al Horford and Luke Kornet — are now elsewhere, leaving only fourth-string option Neemias Queta among the incumbents. New free agent signings Chris Boucher and Luka Garza are expected to compete with Queta for the starting gig. Deep-bench reserve Xavier Tillman and two-way rookie signing Amari Williams could theoretically also lobby for minutes.

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During a new reader mailbag, Brian Robb of MassLive breaks down how Boston could have retained Horford this season.

"The Celtics definitely could have afforded that purely based on salary, but the fact that they are a repeater tax team this year complicates the finances a bit. Currently, Boston is $12 million over the tax threshold, but every additional dollar they spend now on the team would cost $5.50 in repeater tax penalties. That fact undoubtedly impacted what Boston was willing to offer Horford during a year in which the Celtics aren’t expected to have Tatum available much, if at all."

Robb notes that, although general manager Brad Stevens did tender new contract offers to departed free agents Horford and Kornet, he hinted that the monetary value was little more than the veteran's minimum, which is what Boucher and Garza signed on to take.

Should Boston Have Tried Harder to Retain Al Horford?

"The case could be made that the Celtics should have prioritized paying Horford a bit more and tried other avenues to reduce their luxury tax burden," Robb writes.

Horford ultimately agreed to a two-year deal to serve as the Golden State Warriors' likely new starting center.

Sharpshooting forward Sam Hauser — on a reasonable four-year, $45 million contract — and veteran combo guard Anfernee Simons — on an expiring $27.7 million deal — both might have made more sense to move, Robb submits. It's still possible that one or both players won't be on the Celtics' roster to close out the season, as the team looks to dip under the NBA's still-punitive first luxury tax apron.

That said, Robb wonders if Horford would have even been interested in signing on to the mid-level exception deal he eventually agreed to in Golden State. With six-time All-Star Jayson Tatum slated to miss most or all of the season and former championship starters Jrue Holiday and Kristaps Porzingis now elsewhere, Boston is likely to take a massive step back from contender status this year.

The 39-year-old Horford is clearly prioritizing playing for his second NBA title, and getting big minutes, to boot.

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On Monday morning, it was reported by Michael Scotto of HoopsHype that Horford's two-season, $12 million contract with Golden State includes a 15 percent trade kicker — meaning he'll make an extra 15 percent of his salary if he is dealt in either year of the deal. In fairness, most players waive their trade kickers as a sign of faith for their new teams, but they're certainly under no actualy obligation to do so.

Update: Al Horford has a 15 percent trade kicker included in his two-year, $12 million deal with the Golden State Warriors, league sources told @hoopshype. Horford also has a player option, as previously reported. https://t.co/ia0iJ4nqlu
— Michael Scotto (@MikeAScotto) October 6, 2025

Horford remains a reliable two-way contributor, even heading into his 19th NBA season. Should Boston have held onto him, in an effort to still compete in a wide-open Eastern Conference? Perhaps.

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