Adams, 34, had the longest tenure of any Cowboys player. He was a second-round pick in 1998 out of Michigan State and was a five-time Pro Bowl selection. He missed only 14 games in his 12-year career with Dallas.
"I have never experienced what it is like to have a team that doesn't enjoy excellent play at the left tackle position," Cowboys owner/general manager Jerry Jones said in a statement released by the team. "When we first selected Flozell, we thought we would move Larry Allen to left tackle, but that never happened because Flo was able to step right in and play at a high level very early on in his career."
But in 2009, Adams wasn't as dominant, and the organization began looking at other options. Doug Free spent some time at left tackle during practices and games, and when Adams suffered a calf injury in Dallas' playoff loss to Minnesota, Free took over.
Adams was due a $2.5 million roster bonus in June and a base salary of $5 million this season. To improve his ability to catch on with another team, Adams requested his release through agent Jordan Woy once it became apparent Jones would eventually cut the veteran player.
"I asked them to make the move early if they were going to do it," Woy said. "We requested it, but they did it on their own timetable. With no cap this year, the acceleration doesn't hurt them."
Hamlin was coming off an average season in which he finished with 74 tackles, no interceptions and four pass breakups. His 2010 base salary was scheduled to be $5.596 million.
"I would like to say to all my fans that I appreciate all the love that you have showed me in Dallas," Hamlin said via his Twitter page. "It was a good run..... Thanks."
Adams and Hamlin did not return calls seeking comment.
It was an interesting week for Hamlin, who missed the first day of voluntary workouts because his scheduled flight out of Los Angeles didn't allow him to get to Dallas on time. Hamlin, along with wide receiver Miles Austin and cornerback Terence Newman, had spent the weekend with several other NFL players attending the Playboy Golf Scramble at the Industry Hills Golf Club at Pacific Palms Resort in Industry Hills, Calif.
Hamlin signed a one-year contract in 2007 after spending four seasons in Seattle. Hamlin earned his first Pro Bowl berth that year, compiling career highs in tackles (102) and interceptions (five). The Cowboys rewarded Hamlin with a six-year, $39 million contract.
But Hamlin's numbers declined in 2008, when he had 92 tackles and just one interception. Last season, he missed four games with a high ankle sprain and was replaced by Alan Ball. At the time, coach Wade Phillips praised Ball's work for getting the secondary in place and for making plays.
Hamlin returned for the final three games of the regular season and had 15 tackles and one pass breakup. Phillips said Hamlin was playing better toward the end of the season.
"He is a smart player who was valuable to us in playing the role of the quarterback in the secondary," Jones said about Hamlin in the statement. "We appreciate what he brought to this team -- and this defense -- as a solid player and a competitor."
The Cowboys have a few options at safety in Mike Hamlin and Ball.
Ken Hamlin and Adams did not appear for workouts scheduled for Friday at Valley Ranch.
ESPN reporter Ed Werder contributed information to this story.