The move doesn't come as a major surprise. Williams had a nonguaranteed $947,907 contract for 2013-14, but the first $200,000 was set to become guaranteed after Sunday.
And with an abundance of players heading to Boston once the blockbuster trade with the Brooklyn Nets goes through, the Celtics freed up a roster spot by cutting ties with the 6-foot-6 guard-forward.
Williams, 26, appeared in 24 regular-season games for Boston last season, averaging 4.6 points, 1.8 rebounds and 1.6 assists per game. He was arrested in May for allegedly brandishing a gun during a visitation exchange with the mother of his child in Kent, Wash., though charges have yet to be filed in the case.
Information from ESPNBoston.com's Chris Forsberg was used in this report.
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