It's always been considered unlikely that the Boston Celtics and Jaylen Brown would reach a deal on a contract extension, the franchise just doesn't do that (the last one was Rajon Rondo). That said, Boston would love to get him locked up on a number they like.
The Celtics made a four-year, $80 million offer to Brown but he turned it down, reports Chris Haynes of Yahoo Sports.
Brown sounded like a guy wanting to bet on himself speaking to The New York Times' Marc Stein:
Brown impressed this past summer with Team USA - where he was aggressive and attacking - and now is back with Boston (where Kemba Walker replaces Kyrie Irving at the point, hopefully leading to better chemistry on the court). There is an expectation Brown is going to return to the upward trajectory we saw in his second NBA season, and for stretches the second half of last season.
If Brown takes those steps forward this season he will hit free agency next July in what will be a down market. A young forward with his skills could interest a team such as Atlanta - a team with cap space, young players, and it's Brown's home state - or others, and if so they are coming in with a larger offer intended to make the Celtics balk (Boston has the right to match any offer, Brown is a restricted free agent).
Do other teams see Brown as worth more than the $80 million Boston put on the table? We will not know until next summer, but it sounds like Brown is willing to make the bet the answer is yes.