(Undated) -- The USC Trojans are landing one of the top transfer quarterbacks in the nation. Caleb Williams announced Tuesday that he will transfer to USC after entering the portal in early January. Williams played last season at Oklahoma and will reunite with former Sooners head coach Lincoln Riley. Williams threw for 1,912 yards, 21 touchdowns and four picks as a true freshman at OU. He picked the Trojans over UCLA, Wisconsin, Georgia and a possible return to Oklahoma. Williams told ESPN he wants to "help bring USC back to being a top-rated program."