The season-ending move was included on the NFL's transaction list Tuesday, a day after the fifth-year player was placed on the waived-injured list. Williams has four years left on his contract, but his future in Buffalo is uncertain.
The Bills gave up a sixth-round pick to acquire the Buffalo native in a trade with Tampa Bay in April. Williams' playing time had diminished before he hurt his left calf in practice last week.
He was inactive in four of Buffalo's past eight games, and has eight catches for 142 yards and a touchdown this season.
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