BOSTON (AP) The Celtics were in sunny Los Angeles, it was another sub-zero winter day back in Boston, and Gordon Hayward was stuck in rehab, shooting baskets from a chair and picking up marbles with his toes to work his surgically repaired ankle back into shape.

"The hardest part of the whole process has been the mental challenge," Hayward said Thursday, reporting that he is 100 percent healthy and preparing to be on the court for the Oct. 16 opener against the Philadelphia 76ers. "I think you find the fight within yourself."

The Celtics' top free-agent acquisition of the 2017 summer, Hayward was injured in the first quarter of the first game of the season when he landed awkwardly on his left leg, breaking his tibia and dislocating his ankle. He may have been able to return before the end of the season, but then he needed more surgery in May.