SANTA CLARA, Calif. – The San Francisco 49ers' preparation for Sunday's game at Tennessee took a slight turn when Titans quarterback Jake Locker returned to practice Wednesday.Locker has been out for the past two weeks with hip and knee injuries, and the Titans still plan to start Ryan Fitzpatrick on Sunday.Nevertheless, 49ers coach Jim Harbaugh said the team has to be aware that Locker could play, however unlikely that might be.