The Texans have lost a number of players in free agency, including outside linebacker Mario Williams to Buffalo, guard Mike Brisiel to Oakland and cornerback Jason Allen to Cincinnati. Houston also traded linebacker DeMeco Ryans to Philadelphia for a fourth-round draft choice and an exchange of third-round picks. "Obviously, it's been a difficult 10 days," coach Gary Kubiak said. "We've lost some key players who are tremendous people and leaders. They played a big part in our building process. "It's going to be difficult to replace them, but obviously we have to move on and other players have to step up."