A little over a year ago, the Boston Celtics were riding high.

The team had claimed its NBA record-extending 18th franchise championship to cap off a 64-win season, and looked primed to be able to contend for years to come, sporting a deluxe top seven of All-NBA forward Jayson Tatum, All-Star wing Jaylen Brown, All-Defensive guards Derrick White and Jrue Holiday, former All-Star big men Kristaps Porzingis and Al Horford, and future Sixth Man of the Year Payton Pritchard.

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One Tatum Achilles tendon tear later, Boston is on shakier ground. Team president Brad Stevens traded away Holiday and Porzingis, and appears poised to let Horford go the way of fellow reserve center Luke Kornet and depart in free agency this offseason.

ESPN’s three-year outlook for the cost-cutting Celtics has declined precipitously, from No. 2 last season to No. 13 this year. ESPN NBA insider Tim Bontemps explains why.

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“A year ago, the Celtics were the defending champions en route to dominating the Eastern Conference for years,” Bontemps writes. “Then, Jayson Tatum tore his Achilles in May, Boston failed to get out of the second round and the team traded Porzingis and Jrue Holiday this summer.”

“It’s a reminder of how quickly things can change in the NBA, even though a core of Tatum, Jaylen Brown and Derrick White — plus strong management in coach Joe Mazzulla and president of basketball operations Brad Stevens — portends a quick bounce-back, assuming Tatum is healthy, as expected, in 2026-27,” Bontemps writes.

This story will be updated…

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