Greg Knapp will return to Oakland as offensive coordinator.

Knapp, the quarterbacks coach for the last two seasons with the Houston Texans and the Raiders offensive coordinator in 2007 and 2008, replaces Al Saunders, who remains under contract. It’s unclear if Saunders will still have a role with the team.

Raiders coach Dennis Allen declined to confirm Knapp’s hiring in a morning radio appearance on KNBR and the club made no announcements regarding the coaching staff. The NFL Network first reported Knapp’s signing, and a source familiar with the situation characterized it as a“ done deal.”

Knapp was the offensive coordinator in Atlanta when Allen was on Jim Mora’s staff from 2004 through 2006 and has also served in that capacity with the 49ers (2001-2003) and Seattle Seahawks (2010).

Hired by Lane Kiffin by Oakland in 2007, Knapp did not call plays with the Raiders until Kiffin was fired four games into his second season, and later in the season was replaced by head coach Tom Cable as the play-caller as the Oakland offense struggled with JaMarcus Russell at quarterback.

Knapp was offensive coordinator for the San Francisco 49ers from 2001-03 and worked with Raiders coach Dennis Allen with the Atlanta Falcons, where both were working under Mora.

According to Foxsports.com, Allen has interviewed former San Diego Chargers and 49ers defensive coordinator Greg Manusky for that position in Oakland, and that Kelly Skipper will remain on staff. Skipper has coached both tight ends and running backs in his five years with the Raiders.

ESPN reported Allen’s request to speak with Broncos linebackers coach Richard Smith for the defensive coordinator’s job was denied. The Raiders have also been linked with 49ers secondary coach Ed Donatell, who worked with Allen in Atlanta and has also been a defensive coordinator for the Packers.

Donatell has been with the 49ers just one season and chances are he remains under contract, meaning San Francisco could deny permission to speak with him. The 49ers as a matter of policy do not divulge the contract status of coaches or if teams have asked to speak with their coaches.

Tight ends coach Adam Henry joined special teams coach John Fassel (Rams), defensive coach Mike Waufle (Rams) and wide receivers coach Sanjay Lal (Jets) as assistants who have found new jobs. Henry will coach wide receivers at LSU.