Merriman was placed on the injured reserve list because of a calf injury and a "minor-injury designation" last month. The Chargers said when announcing the move that Merriman must be released once he's healthy.
General manager A.J. Smith, who hasn't been a fan of Merriman's celebrity-leaning lifestyle, didn't return a call from The Associated Press seeking comment. Merriman didn't return an e-mail seeking comment.
Known as "Lights Out" because of his once-ferocious hits, Merriman had 39½ sacks in his first three seasons. He's had only four in the three seasons since then due to a variety of injuries.
He was suspended for four games in 2006 after testing positive for steroids. Even missing the four games, he had 17 sacks that year. Merriman blamed the positive test on a tainted supplement, which he never identified.
He also brought unwanted attention off the field. He was arrested just before the 2009 season after 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.
Merriman missed most of the 2008 season after undergoing reconstructive knee surgery. He had four sacks last year as he tried to regain his hard-hitting form. After sitting out most offseason workouts and part of training camp to protest his contract status, he was slowed by an Achilles injury and then a calf injury.
He had only five tackles and no sacks in limited action this year.
Davis has been one of Smith's most questionable draft picks, failing to live up to his billing as the team's first-round pick in 2007. Davis had 21 catches for 259 yards and one touchdown this season. He started one game and was inactive for Sunday's 33-25 victory against Tennessee.
His four-season totals are 51 catches for 558 yards and two touchdowns. He has played in only 26 games, 14 coming in his rookie season, with two starts.
He also was placed on IR in 2008 after playing in just four games, and played in only one game last season.
Information from The Associated Press was used in this report.