Thomas, a seven-time Pro Bowler in 12 seasons with the Miami Dolphins, was released last week and had already received to two offers, one from the New Orleans Saints, the other from New England.
He received his third offer within the last 24 hours from the Cowboys after meeting with owner Jerry Jones at the NFL Combine in Indianapolis.
It didn't take him long to figure out where he wanted to spend his next season in the NFL - Dallas.
Thomas' contract is a one-year deal worth $3 million total, including a $1 million signing bonus, $1 million in base salary and $1 million in incentives.
Thomas is from Pampa, Texas and played his college football at Texas Tech. He was selected in the fifth round of the 1996 draft. One of the reasons he signed with the Cowboys was because he wanted to return to his home state of Texas.
"Zach being from Texas was a huge advantage," Thomas' agent Drew Rosenhaus told TheRanchReport.com. "Plus he really really likes Wade Phillips. I think this is a perfect fit for him. This is really good."
Cowboys head coach Wade Phillips is a Zach Thomas fan from way back. Thomas, who many consider to be an undersized, overachieving force with the Dolphins in his first 12 years in the league, will be an intriguing fit into the Cowboys' 3-4 scheme.
In San Diego, Phillips used the undersized Donnie Edwards effectively at inside linebacker, a role that Thomas will likely play with the Cowboys.
Thomas will be expected to compete with Akin Ayodele and Kevin Burnett for a starting role opposite Bradie James.
"Zach has more tackles than anyone in the Pro Football Hall of Fame so you don't want him wasting time on linemen you want him making plays, finishing plays, tackling guys," said Rosenhaus. "Zach watched a lot of tape on all the teams, but coming here and meeting with Wade, looking him in the eyes and and discussing that defense was big for us."
However, keep in mind Thomas' 2007 season was prematurely ended by a concussion. For the year, he played in just five games, recording 42 tackles and one sack.
His last Pro Bowl season was in 2006, when he recorded 103 total tackles, three sacks and an interception.
Looking at his age and his health, the question has to be asked, can he hold up through and entire 16-game regular season schedule in the rough and rugged NFC East? And does he still have gas left in the tank after 12 years in the league?
Time will only tell.
The one thing we do know is the 12-year veteran says he is healthy and ready to go -- a fact confirmed by the decisions of three teams to move in with contracts in the last week.
Thomas also underwent a physical Saturday and passed with no problems, TheRanchReport.com has learned.
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