The Cowboys utilize a 3-4 defense under head coach Wade Phillips, and Thomas has said he prefers that system to the 4-3.
If Thomas indeed signs with the Cowboys, it means he probably would never his face his former team because the Dolphins aren't scheduled to face Dallas until the 2011 season.
TRADE TALK: Former first-round picks DeAngelo Hall and Troy Williams both are being shopped by their team, and the Dolphins sure could use either.
That's particularly true for Hall, a cornerback from Atlanta. He's one of the best in the business, although he has a reputation as being difficult to manage and he also only has one year left on his contract.
As for Williamson, he has been a major disappointment since being the seventh overall pick by Minnesota a couple of years ago, but Vikings coach Brad Childress thinks a change of scenery might do him some good.
The price for Williamson probably isn't more than a third- or fourth-round pick. There's word the New York Giants are prepared to offer their No. 1 pick, the 31st overall, to Atlanta for Hall.
DOLPHINS SALE: The Dolphins have a new co-owner in Stephen Ross, who before too long will replace Wayne Huizenga as the majority owner.
Huizenga announced Friday he had sold a 50 percent interest in the team, the stadium and land adjacent the stadium to Ross.
Huizenga said both will have an equal say in Dolphins matters, although Huizenga will have the final word in case of a deadlock.
The plan is for Ross to assume majority control of the team at some point in the future.
Huizenga said he would retain a part of the team until he died, and his family would take over after him.