Al Horford will not exercise his $30.1 million player option on his 19-20 contract with the Boston Celtics. Horford will become an unrestricted free agent.

Horford and the Celtics have mutual interest in working on a new deal in July. Horford could help Boston's salary cap flexibility with a new deal that starts below that $30.1 million salary.

Horford joined the Celtics as a free agent in 2016.