The Raiders have made the three previously reported acquisitions official. Those signings were DB Phillip Adams, LB Keenan Clayton and T Willie Smith. To make room for those three, the team waived CB Chimdi Chekwa and CB Bryan McCann, and waived/injured DT Jamie Cumbie.

Adams faced off against the Raiders Thursday as a member of the Seahawks. The 5-11, 195 corner played in 22 career games in two seasons with San Francisco, New England and Seattle. He was the 49ers' seventh-round selection in the 2010 NFL Draft out of South Carolina State. He can also return kicks.

Clayton (6-1, 230) played in 21 games with one start in two seasons with Philadelphia. He was the Eagles' fourth-round draft pick out of Oklahoma in 2010.Smith (6-5, 310) played in four games with three starts for Washington last year. He joined the Redskins as a non-drafted free agent out of East Carolina in 2011.

With the signing of Adams and the releasing of McCann and Chekwa, the Raiders currently have six cornerbacks.