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Celtics' New Ownership Sends Message to Joe Mazzulla After News on Tuesday

Originally posted on Athlon Sports | By Matt John | Last updated Aug 19, 2025 5:40 PM ET

The Boston Celtics have made various moves this offseason. While many have been paying attention to the players they've traded away to save money, the Celtics officially announced that they have been sold to new ownership this offseason, over a year after it was announced that owners had planned to sell the team.

The Celtics were previously owned by the Grousbecks, but have officially been sold to Bill Chisholm. The Celtics have been owned by the Grousbecks and their ownership group, Boston Basketball Partners L.L.C., since 2002. In that time, they have seen the team win two championships over the last 23 years.

Before making the sale official, the Celtics also extended Joe Mazzulla this offseason. On August 8, Boston agreed to a multiyear contract extension with Mazzulal (h/t ESPN). The specific terms of the deal have not been disclosed.

After the Celtics' sale was official, Grousbeck delved into why the current Celtics ownership and front office are confident in Mazzulla in an exclusive interview with The Boston Globe's Adam Himmelsbach.

“I think Bill and I both felt, and Brad, that it was a great thing to lock in Joe and have him be happy and empowered,” Grousbeck told Himmelsbach. “We’re trying to empower Joe to be the championship coach that he is."

New: “We want to make sure we have all the firepower necessary to chase championships.”

I spoke with Bill Chisholm and Wyc Grousbeck about the sale being finalized and where things go from here.

https://t.co/FMC6yZ2ssC
— Adam Himmelsbach (@AdamHimmelsbach) August 19, 2025

Joe Mazzulla's Success as Celtics' Head Coach Speaks for Itself

Mazzulla was thrust into the position of Celtics head coach days before training camp was about to start for the 2022-23 season. Because of Ime Udoka's indefinite suspension, Mazzulla became their interim head coach.

He didn't have any previous head coaching experience, as he had been on the Celtics' coaching staff since 2019. However, Mazzulla did a solid job keeping the ship afloat, as the Celtics got the No. 2 seed in the Eastern Conference and were within a game of returning to the NBA Finals in 2023.

Since then, Boston has won a title as the No. 1 seed in 2024 and got the No. 2 seed in 2025, though their latest playoff run ended in the Eastern Conference Semifinals at the hands of the New York Knicks.

Because the Celtics have consistently been successful with Mazzulla calling the shots from the sidelines, despite their most recent playoff run not going their way, the team is confident in Mazzulla's abilities. This season will be different with Jayson Tatum out indefinitely, but Boston demonstrated their belief in their head coach despite that obstacle.

This article first appeared on Athlon Sports and was syndicated with permission.

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