General manager Buddy Nix said the decision was based in part on the potential the Bills saw in two younger players who had been competing with Merriman for the fourth defensive end spot.
"We think we've been patient, but it comes to a point where we felt like we needed to move on and look down the road," Nix said shortly before the Bills returned to practice from a two-day break. "We need to look past this week. We need to look further down the road."
Though Nix wouldn't say which two players were competing for the roster spot left open by Merriman's release, the Bills' latest depth chart had Robert Eddins move up into the backup position behind Mario Williams.
Kyle Moore, a third-year player signed off Detroit's practice squad last November, has also looked impressive through the first month of training camp.
Nix said Merriman's health wasn't an issue and added he made the move now to provide the player a better chance to sign with another team.
The move does allow the Bills (No. 19 in the AP Pro32) to save a portion of the $4 million salary Merriman was scheduled to make in the final year of his contract.
Merriman's release was regarded as a mild surprise for a former three-time Pro Bowl selection, who described himself as being in his best shape in years after having season-ending surgery in November to repair a partially torn right Achilles tendon. It's an injury that had nagged him for much of the previous two seasons.
The Bills had kept their faith in Merriman, believing the 28-year-old had an opportunity to play a key backup role on a defensive line that was revamped in free agency this off-season with an eye on pressuring quarterbacks.
Buffalo signed Williams to a six-year, $100 million contract, and then landed pass-rushing defensive end Mark Anderson.
Merriman had spent much of training camp backing up both Williams and Anderson.
Merriman posted a note on his Twitter account shortly after being released, thanking the team, coaches, his teammates and fans for his time in Buffalo.
Though Merriman missed a few practices nursing a twisted ankle and sore hamstring, the Bills gave no indication his job was in jeopardy.
Merriman was credited with three tackles in two preseason games. He had one tackle and played with the backups well into the second half of Buffalo's 36-14 loss at Minnesota on Friday.
Coach Chan Gailey called Merriman expendable because the Bills have three veteran defensive ends, including Chris Kelsay, allowing the team the opportunity to develop a younger player.
"He was doing a good job, but it wasn't where we thought he needed to be as far as the other guys that were playing the position," Gailey said.
He also questioned whether Merriman was better suited to play the linebacker spot in a 3-4 defence, as opposed to trying to fit in as a defensive end after the Bills made the switch to a 4-3 this off-season.
The seventh-year player was entering his third season in Buffalo. The Bills claimed him off waivers after he was cut by San Diego in November 2010.
He finished the 2010 season on injured reserve after aggravating the injury to his Achilles tendon a half hour into his first practice with Buffalo. Merriman had two sacks in five starts with the Bills last season before landing on IR to have surgery on his Achilles and also repair a nagging shoulder injury.
Merriman, on numerous occasions this off-season, suggested he felt rejuvenated.
"I feel young," Merriman said in May. "Anybody that will get a chance to watch me this year will see I'm moving around as I did when I came into the league."
The NFL's 2005 defensive rookie of the year, Merriman was at his peak upon breaking into the NFL after being drafted 12th overall by San Diego.
He earned the nickname "Lights Out," after generating 39 1/2 sacks through his first three seasons before injuries slowed his production. Merriman combined for just six sacks in his past four seasons, a stretch in which he appeared in only 23 games.
Gailey credited Merriman for his perseverance in the face of injuries.
"He did a great job of fighting back from where he was," Gailey said. "I've got to give him a lot of credit because it would've been easy to bail."
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