ORCHARD PARK, N.Y. (AP) -- The Buffalo Bills have secured at least one half of their starting safety tandem after signing Aaron Williams to a four-year, $26 million contract extension Wednesday.
A person with knowledge of the contract said Williams is guaranteed $14.625 million. The person spoke on condition of anonymity because the terms were not released by the Bills.
The extension locks up Williams through 2018, and comes at a time when the Bills risk losing three-time Pro Bowl safety Jairus Byrd, who is preparing to test free agency next week.
''I told them I accept the role of leading this defense to where it used to be,'' Williams said. ''I'm just blessed that they gave me that opportunity, and they trusted me to be here long-term to get this team back to where it started.''
Williams, Buffalo's second-round pick in the 2011 draft, was entering the final year of his contract. He was rewarded with the extension after successfully making the switch from cornerback to safety last season.
In 14 games last year, Williams had a career-best 82 tackles and tied Byrd for the team lead with four interceptions.
Overall, he has five interceptions and two forced fumbles in 34 career games.
''Aaron is the type of young, core player we targeted early in the process to retain for years to come,'' general manager Doug Whaley said in a released statement. ''We expect Aaron to continue to grow into a key contributor for the Bills' organization.''
The question is whether Williams will continue to develop alongside Byrd.
This week, the Bills decided against applying the franchise tag for a second consecutive year to retain Byrd's rights, opening the door for the fifth-year player to test free agency on March 11.
Williams is hoping the Bills can still reach a deal to re-sign Byrd, because the two established a solid on-field rapport last season.
''If Jairus does come back, that would be the greatest thing ever, because our chemistry is unbelievable,'' Williams said. ''If he doesn't come back, good luck to him. We're always going to be best friends. ... We'll just have to move on and find another piece to try to replace his role.''
The Bills defense is undergoing another offseason change, with Jim Schwartz taking over as coordinator after Mike Pettine left to become the Cleveland Browns head coach. Schwartz has a similar aggressive defensive coaching philosophy, which is expected to ease the transition.
''I feel real confident that nothing major is going to change,'' Williams said. ''There might be a few things here and there, but I think team-wise, once we get all the pieces together we will be fine.''
The Bills also announced free-agent linebacker Jameel McClain had arrived in Buffalo to meet with team. Listed at 6-foot-1 and 245 pounds, McLain spent the past six seasons with the Baltimore Ravens before being released by the team last week.
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