Bill Simmons Blames Joe Mazzulla After Celtics' Playoff Exit

Bill Simmons is putting a lot of Boston's playoff collapse on Joe Mazzulla. After the Celtics blew a 3-1 lead to the 76ers, Simmons argued that the series slipped away because Boston moved away from the style that made it so good during the regular season. He praised Mazzulla's regular-season work and even said he voted for him as Coach of the Year, but the playoffs left him confused.

For Simmons, the issue was not just that Boston lost. It was how the Celtics played, the decisions they made, and the way their identity seemed to change when the pressure was highest.

"I really think Mazzulla screwed the series up and I'm always going to think that."@BillSimmons reacts to Boston's first-round series collapse against the 76ers. pic.twitter.com/yDr5qLvSbm

— The Ringer (@ringer) May 4, 2026

In a recent podcast, Simmons shared his thoughts on the Celtics exit. He said, "I thought Mazzulla was incredible in the regular season. I voted for him for coach of the year. I thought he was incredible. I don't know what they were thinking with this playoffs. They went back to their 2024 style without the same players… I really think Mazzulla screwed the series up and I'm always going to think that."

What Did the Celtics Do Differently According to Simmons?

Bill Simmons felt Boston's biggest mistake was that it stopped playing like the team that had been so good all season.

In his view, the Celtics slowed the game down, lost their pace, and moved away from the bench units that had given them so much energy during the regular season. Simmons argued that Joe Mazzulla almost treated the series like an experiment, trying to see what would work later in the playoffs instead of sticking with what had already been working.

The biggest issue, according to Simmons, was the rotation. He believed Boston's bench had been one of its real strengths, especially when players like Hugo Gonzalez and Jordan Walsh came in for short, chaotic bursts and changed the feel of games.

Instead, Simmons felt Mazzulla shortened the rotation, leaned into an older 2024-style approach, and then suddenly expected those same bench players to deliver in Game 7 after not trusting them enough earlier in the series. Ultimately, this led to the Celtics bowing out after the very first round of the NBA playoffs.

Related: Jaylen Brown Doubles Down on Joel Embiid Criticism After Playoff Exit

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This story was originally published May 4, 2026 at 12:32 AM.