Sources said the Heisman Trophy winner was scheduled to visit the Raiders next week and would likely sign on as a backup to fellow USC alum Carson Palmer.
ESPN said Leinart would be penciled into the No. 2 slot ahead of Terrell Pryor.
Leinart last played with the Houston Texans after seeing only modest success with the Arizona Cardinals.
Megyn Kelly: Santa Claus and Jesus are both white men
Video of Victoria’s Secret models trying to 'twerk' hits Instagram