The former fourth-round pick, who was traded to the Bills from Tampa Bay this past April for a sixth-round pick, injured his calf last week during practice, though that likely was not the motivation for the decision.
The 27-year-old, who had 11 touchdowns as a rookie and nine during his 2012 season, had just eight catches in 2014. He has been active in just four of the past eight games the Bills have played.
There's no doubt Williams has talent. When the Bills were openly shopping him a few weeks back, there was some interest, though not enough to generate a trade. Assuming he reaches a settlement in Buffalo and becomes a free agent, it wouldn't be surprising to see him end up on a roster before the end of the season.
In his NFL career, Williams had the most success under Raheem Morris but started to see his production drop under the watchful eye of disciplinarians like Greg Schiano and Marrone. Perhaps a different vibe will unlock what is left of his potential.