The move was made Wednesday, a day after Merriman was placed on 24-hour waivers by San Diego.
Buffalo (0-7) had the first option on acquiring Merriman, a three-time Pro Bowler; the waiver order is based on teams’ records.
The move was made by the first-year general manager Buddy Nix, who is familiar with Merriman. Nix previously worked in the Chargers’ front office when the team drafted him as the 12th overall pick in 2005.
It is unclear when Merriman, 26, will join the Bills, who play the Chicago Bears in Toronto on Sunday.
“He has been an impact player in a 3-4 defense, and we feel this is a good opportunity to make our team better,” Nix said in a statement released by the team.
Known as Lights Out, Merriman has 43 ½ sacks in 60 career games — but only four since sustaining a serious knee injury in training camp in 2008.
Injuries and on- and off-field controversies combined to end Merriman’s tenure in San Diego. Merriman was suspended four games in 2006 after testing positive for steroids, blaming the positive test on a tainted supplement. He was arrested just before the 2009 season after the reality television star Tila Tequila accused him of battery and false imprisonment at his suburban San Diego home. No charges were filed, and Merriman and Tequila settled dueling lawsuits.
The decision to waive him came three weeks ago, when San Diego placed him on the injured reserve list because of a calf injury. Merriman went on the list with a minor-injury designation, meaning he was to be released once healthy. In claiming him, the Bills pick up what is left of his one-year, $3.27 million contract.
Despite the Bills’ getting off to their worst start in 26 years, the decision to claim Merriman is an eye-opener. Nix previously said he was not interested in adding high-profile players and instead was focused on rebuilding through the draft.
Of course, Merriman can serve as a one-year quick fix to bolster a defense that is both porous against the run and having difficulty generating a pass rush. Buffalo allows nearly 189 yards rushing per game, and the Bills have managed only 11 sacks.
HOPING ASOMUGHA CAN PLAY Cornerback Nnamdi Asomugha missed practice, but Raiders Coach Tom Cable said he was hopeful Asomugha would be able to play in Oakland’s game against Kansas City on Sunday.
Asomugha injured himself early in the fourth quarter of last Sunday’s 35-7 win over the Seattle Seahawks when he stepped on the foot of wide receiver Golden Tate. Asomugha has not missed a start since sitting out the final game of the 2008 season.
EAGLES’ JACKSON PRACTICES Philadelphia Eagles wide receiver DeSean Jackson passed post-concussion testing and practiced. He could play against Indianapolis on Sunday. It was Jackson’s first full practice since sustaining a concussion on Oct. 17 in a head-on collision with Atlanta cornerback Dunta Robinson, who also sustained a concussion on the hit and returned to practice for the first time Wednesday.
EAGLES’ SIMS FINED FOR HIT Eagles linebacker Ernie Sims, a repeat offender, has been fined $50,000 for striking a defenseless receiver, Lavelle Hawkins, in Philadelphia’s game against the Titans on Oct. 24. It is the first large fine handed out by the N.F.L. since it sent a video to teams emphasizing what hits would bring big fines and possible suspensions.