Per Brian Robb of Boston Sports Journal, the Celtics are "very interested" in a long-term deal with Hayward regardless of whether he picks up his 2020-21 player option or not.
General manager Danny Ainge has been reluctant to go past a certain point with some players in free agency. Last summer, for instance, Steve Bulpett of the Boston Herald reported Al Horford was negotiating a three-year extension to remain with the team rather than opt in to his $30.1 million option for 2019-20.
ESPN's Adrian Wojnarowski reported negotiations were too far apart between the C's and the then-32-year-old Horford, who wound up signing a four-year, $97 million deal from the Philadelphia 76ers.
Hayward is having his best season since signing with the Celtics in July 2017. The 29-year-old is averaging 17.2 points and a career-high 6.6 rebounds per game with a 51.4 shooting percentage and 39.3 three-point percentage.
One reason for Hayward's success is staying healthy. He missed 13 straight games from Nov. 11 to Dec. 6 with a fractured finger but has played in 28 of Boston's past 32 games since Dec. 9.
Celtics head coach Brad Stevens struggled to integrate Hayward into the rotation last season when he was still working his way back from the fractured tibia and dislocated ankle suffered in the first game of the 2017-18 campaign.
Hayward's performance so far opens things up for him this summer, when he can exercise his $34.187 million player option.
The Celtics have built a strong core with Hayward, Jaylen Brown, Jayson Tatum and Kemba Walker. That group has led the team to the third-best record in the Eastern Conference thus far (37-16).