Boston – Jaylen Brown has reached a landmark agreement on a five-year supermax contract extension worth $304 million. It now stands as the most lucrative contract in the history of the NBA signed by the talented star of the Boston Celtics. The negotiation process concluded after a crucial meeting between Jaylen Brown, his agent Jason Glushon, and Celtics management, to be with the team until the conclusion of the 2028-2029 season.