The Texans auditioned free agent cornerbacks Teddy Williams and Zack Sanchez, according to league sources not authorized to speak publicly.
Starting cornerback Kevin Johnson is in the NFL concussion protocol after suffering a concussion Saturday night against the San Francisco 49ers. Johnson's symptoms are subsiding.
"Kevin is doing good," Texans coach Bill O'Brien said. "Kevin was in here, doing better. Yes, he's doing much better."
Undrafted rookie cornerback Josh Thornton got hurt against the 49ers, too.
A Tyler native who attended Texas-San Antonio, Williams, 30, is a big corner at 6-1, 207 pounds He has played for the Dallas Cowboys, Arizona Cardinals, Chicago Bears, Jacksonville Jaguar, Carolina Panthers and New York Giants.