High-priced defensive end Mario Williams is out in Buffalo, while the Bills aren't giving up on re-signing left tackle Cordy Glenn.

The Bills released Williams and retained the rights to Glenn by designating him their franchise player on Tuesday in a series of moves made a week before the NFL's free-agency period opens.

Neither move was a surprise.

By releasing Williams, the salary cap-strapped Bills freed up nearly $13 million US in payroll next season. He had two years left on the six-year, $100-million contract, and was scheduled to make an $11.5-million base salary this year.

Williams's departure opened room for Buffalo to tag Glenn, who was eligible to become an unrestricted free agent. The $13.7-million designation is essentially a one-year contract offer which Glenn can sign or negotiate a longer-term deal with Buffalo.

Glenn was selected in the second round of the 2012 draft out of Georgia, and has started 61 games for Buffalo. Last year, he was part of a line that helped the Bills lead the league with 2,432 yards rushing.

The Bills also released offensive guard Kraig Urbik and running back Boobie Dixon.

"Days like this are never easy," general manager Doug Whaley said in a statement regarding the departing players. "We will now focus our attention on moving forward as we continue to prepare for free agency, the upcoming draft and the 2016 season."

Williams's days were numbered in Buffalo even before last season ended. His contract was deemed too expensive for a player whose production was dropping. Williams looked disinterested at times, complained about having to drop back into coverage on occasion, and openly questioned whether he fit in the defence.

He finished with five sacks last year, the fewest Williams managed in a season in which he played in at least 13 games since he had 4½ as a rookie in 2006.

Head coach Rex Ryan acknowledged the defence's production was a disappointment in a season Buffalo went 8-8 and extended the NFL's longest active playoff drought to 16 seasons. The Bills finished 19th in yards allowed after finishing fourth a year earlier, and got just 21 sacks, a franchise low for a 16-game season.

Though Ryan defended Williams's performance during the season, he hinted afterward he wasn't pleased with some of the criticism. Without mentioning any player by name last month, Ryan defended his scheme by saying it relies on teamwork.

"I've always had a system that relies on players, putting our players in the best position to be successful for all 11, not one," Ryan said. "It's not just built for one man. It's built for all 11 men."

Ryan vows his defence will be better next season, and has already made several additions to his staff. Last month, he hired his twin brother Rob to be an assistant head coach in charge of the defence, and added former star safety Ed Reed to coach defensive backs.

Williams arrived in Buffalo with plenty of fanfare in March 2012 during a three-day stretch it took for the two sides to negotiate what at the time was the most expensive contract for a defensive player. The value of the deal was a significant departure for a Bills team that had previously taken a modest approach to free agency.

Selected with the No. 1 pick in the 2006 draft, Williams spent his first six seasons in Houston, where he established himself as one of the NFL's top pass-rushers. He had 43 sacks in 63 games, including a career-best 14½ in 2014. He also was part of a powerful defensive front that combined for an NFL-leading 111 sacks in 2013-14.

White cut after decade in Atlanta

The Atlanta Falcons released Roddy White, the leading receiver in franchise history, on Wednesday following his least productive season in a decade.

White's role in the offense declined in 2015 under first-year coach Dan Quinn and offensive coordinator Kyle Shanahan.

The Falcons announced the release of White, 34, in a statement which included glowing compliments from team owner Arthur Blank, general manager Thomas Dimitroff and Quinn.

White holds the franchise records for most catches, receiving yards and touchdown catches. The 2005 first-round pick from Alabama-Birmingham soon became one of the team's biggest stars and most popular players.

Blank said White "is one of the greatest players to ever put on a Falcons uniform."