Cooper Flagg remains a Maverick as Celtics’ Brown trade fuels speculation

Cooper Flagg stays put as Celtics’ move sparks wild theory

Cooper Flagg shut down any talk of a Boston move on Wednesday after the Celtics traded Jaylen Brown to the Philadelphia 76ers. **The 2026 NBA Draft’s top pick made it clear he’s staying in Dallas**, where he debuted in March.

What happened?

The Celtics sent Brown to Philadelphia in a blockbuster deal that included Paul George and four draft picks. Fans quickly spun a theory: Boston might be clearing cap space to chase Flagg, whose rookie deal and restricted free-agent rights align with George’s expiring contract.

NBA insider Jake Fischer dismissed the idea during a Bleacher Report livestream on Tuesday. “Craig J89, an out-of-left-field question,” Fischer said after reading a fan’s comment. He acknowledged the timing lines up but stressed Dallas holds all the leverage.

Why it matters for Cooper Flagg

Flagg, the Maine native taken first overall in 2026, has deep ties to Boston. He grew up watching Celtics games at TD Garden and called the arena “incredible” after his March debut. Still, he shut the door on any future with the green-and-white.

“Nah, I love being a Maverick,” Flagg said. “That’s home and I don’t want anything else.”

Dallas controls Flagg’s rights through at least 2030. He can sign a rookie-scale max extension in 2028, and even if talks stall, the Mavericks keep his restricted free-agent rights. That makes a move unlikely unless Flagg himself requests it.

What comes next?

Brad Stevens framed the Brown trade as a cap-flexibility play, not a long-term play for Flagg. “When I looked at our team and where the league was heading, the path looked a little bit more challenging,” Stevens told reporters.

The Celtics now have more cap room and draft capital, but the Flagg speculation is dead-for now. Unless the 20-year-old changes his mind, Dallas will keep its franchise cornerstone through at least the end of the decade.

Flagg’s next steps? Focus on his rookie season and building with Luka Dončić in Dallas. The Mavericks, meanwhile, hold all the cards.