"The Buffalo Bills lost linebacker Paul Posluszny and gained the veteran backup quarterback they were seeking as the NFL free-agency season kicked into gear Tuesday night.

Posluszny agreed to a six-year contract with the Jacksonville Jaguars, his agent said.

Terms were not available and Posluszny can't sign a contract until 6 p.m. Friday. That's the leaguewide start date for free-agent contracts. However, Posluszny has made an oral agreement with the club from the AFC South.

The same situation exists with Miami Dolphins free-agent quarterback Tyler Thigpen, who agreed to terms on a three-year deal with Buffalo. That's a move that has been widely anticipated, because Thigpen enjoyed a measure of success in the 2008 season under Bills coach Chan Gailey when the two were with the Kansas City Chiefs. Thigpen's agent, Joel Turner, confirmed the oral agreement.

Jacksonville plays a 4-3 defensive scheme, and that was the big factor in the decision, said Michael McCartney, Posluszny's Chicago-based agent.

"He got excited to play in a 4-3 defense in the middle," McCartney said. "He's leaving Buffalo with a heavy heart."

"I have so much respect for the Buffalo organization," McCartney said. "They did everything they could to try to sign him. But he felt more comfortable in a 4-3 defense. I want to emphasize how much respect I have for Jim Overdorf (Bills senior vice president of football administration) and the Bills. It was a tough decision.""