Updated

ORCHARD PARK, N.Y. (AP) Safety Aaron Williams' bid to resume his career in Buffalo following a second season-ending neck injury is over after the Bills released the starting safety.

The Bills provided no reason in announcing the move in a one-sentence statement issued Thursday, hours before the NFL's free-agency signing period opened.

The decision comes two months after Williams' father told The Associated Press that his son was leaning toward continuing his career. Aaron Williams also indicated he was planning to return as recently as Wednesday, when he posted a note on his Instagram account congratulating starting quarterback Tyrod Taylor for restructuring his contract and remain in Buffalo.

Williams had two seasons left on his contract and scheduled to make a $3.6 million base salary this season.

The sixth-year starter's season ended last year when he was sidelined by a blindside hit to the head by Dolphins receiver Jarvis Landry in Buffalo's 28-25 loss at Miami on Oct. 23. In 2015, Williams' season was cut short after being hurt attempting to make a diving headfirst tackle. He missed the final 11 games and had neck surgery during which doctors shaved two disks to alleviate nerve damage.

Williams' departure further depletes an already thin secondary. The Bills were not expected to re-sign starting cornerback Stephon Gilmore, while they released backup Nickell Robey-Coleman on Monday.

The Bills did continue adding players.

A person with direct knowledge of the decision has confirmed to The AP that Buffalo agreed to sign offensive lineman Vladimir Ducasse to a three-year contract.

The person spoke to the AP on the condition of anonymity because the Bills have not announced the deal reached before the NFL's free-agent signing period opens on Thursday.

CBSSports.com first reported the agreement.

Ducasse has played a majority of his seven NFL seasons at guard. Buffalo will be his fifth team in five years after he spent last season playing for Baltimore.

Ducasse is familiar with Bills new offensive line coach and run-game coordinator Juan Castillo, who was the Ravens offensive line coach last year.

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