The Celtics are set to give Jaylen Brown the biggest contract extension in NBA history, agreeing to a 5-year, $304 million super-max deal. The contract goes into effect for the 2024-25 season, during which Brown will earn $52.3 million, his agent confirmed Tuesday. The extension runs through the 2028-29 season, when the forward will make $69.1 million. His deal beats the previous record of $276 million given to the Nuggets’ Nikola Jokic last year.