Just a year removed from capturing the franchise’s 18th championship, the Boston Celtics now face a far different offseason outlook — one clouded by injury, capped by financial handcuffs, and complicated by the unforgiving math of the NBA’s new collective bargaining agreement.

Jayson Tatum’s Achilles rupture in the postseason not only derailed Boston’s title defense but now looms over what could be a pivotal summer for president of basketball operations Brad Stevens. Tatum, Jaylen Brown, and Derrick White are all under long-term deals, but the cost of maintaining this contending roster has ballooned to historic levels — and the CBA is making sure the bill comes due.

The Celtics are staring down a $231 million payroll and a projected $263 million in tax penalties. That puts them $22 million over the dreaded second apron — and while billionaire owners can stomach a hefty tax bill, the league’s real deterrent is on the basketball side.

“It’s not the luxury tax bill, it’s the basketball penalties,” former governor Wyc Grousbeck said earlier this year. “The new CBA was designed to stop teams from going crazy.”

Those penalties are steep. No combining contracts in trades. No sending out cash. No sign-and-trades for expensive players. And perhaps most pressing: no ability to trade first-round picks seven years out. Boston’s 2032 first-rounder is already frozen. The 2033 pick could be next if the Celtics remain over the line.

So, what now for Stevens and new majority owner Bill Chisholm?

Three potential paths stand out.

The most conservative: keep the roster intact, at least for now, and kick the tough decisions to the trade deadline. But waiting comes with risk. The Celtics will add two more young players with picks No. 28 and 32, and there’s already a full house with 12 players under contract. If a shakeup becomes necessary midseason, few teams will be able to absorb significant salary without sending money back — and that defeats the purpose of trying to trim payroll.

Option two: stay competitive while slashing costs. That could mean moving Kristaps Porzingis and his $30.7 million expiring deal. He played just 42 games this season and has a trade market, with Brooklyn standing out as a team that could take him on without needing to return a player.

Boston could also explore moving sharpshooter Sam Hauser, whose $6.2 million salary next year carries an $80 million tax hit — yes, you read that right. But even those moves likely keep the team above the apron… just slightly less so.

And then there’s the nuclear option: take a gap year. That would involve trading Brown, the NBA’s highest-paid player, for a combination of draft picks, young talent, and expiring deals. It would sting. But it would also position Boston for a reset around Tatum and White starting in 2026-27, while still retaining their 2026 first-rounder.

In the meantime, there are pressing needs.

With Al Horford and Luke Kornet both hitting free agency and Tatum sidelined into the season, Boston could be dangerously thin in the frontcourt. The team was +19.7 per 100 possessions when Horford and Kornet shared the floor, and both may not be back.

Porzingis is extension-eligible, as are Horford and Jordan Walsh, though don’t expect much movement there with the books already bursting.

Boston has five first-round picks over the next seven years but can trade just one, either 2026 or 2027. It does, however, have flexibility with pick swaps and five second-rounders to work with.

For Stevens and the Celtics, the margin for error is thin. The foundation is still championship-caliber. The finances? A different kind of challenge entirely.