ORCHARD PARK, N.Y. – Starting safety Aaron Williams' career in Buffalo is over after two season-ending neck injuries, and the Bills opened the NFL's free-agency signing period on Thursday by restocking their defensive backfield.

The Bills announced reaching deals with five free agents, including safeties Micah Hyde and Jordan Poyer.

A person with direct knowledge of Hyde's contract told The Associated Press that it's a five-year deal valued at about $30 million and includes $14 million in guaranteed money. The person spoke to The AP on the condition of anonymity because the Bills have not announced the contract's details.

Hyde spent the past four seasons with Green Bay, where he established himself as a versatile player in playing safety and cornerback, and also returning punts. Poyer has four years of NFL experience, and spent the past three-plus seasons in Cleveland.

The Bills also filled their place-kicking vacancy by signing Steven Hauschka, and confirmed previously reported agreements to sign fullback Patrick DiMarco and offensive lineman Vladimir Ducasse. Hauschka has nine seasons of NFL experience and spent the past six in Seattle. He replaces Dan Carpenter who was cut on Monday.

Safety became a key position of need for Buffalo, especially after the team released Williams earlier in the day.

The decision came 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.

Williams thanked Bills fans in a note posted on his Twitter account. He didn't provide any hint toward whether he'll resume playing, except to say: "God has a plan for me; excited for what He has planned for me."

Williams 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.

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

DiMarco agreed to sign a four-year, $8.4 million contract on Wednesday. He's a sixth-year player, who spent the past four seasons in Atlanta, where he was primarily used as a blocking back.