Oakland Raiders head coach Jon Gruden said rookie running back Josh Jacobs (shoulder) isn't a lock to return in Week 15 against the Jaguars despite positive results from his MRI exam. Jacobs's status is unclear for this Sunday, although he was a limited participant in the walkthrough practice on Wednesday. Jacobs must prove to Gruden and the coaching staff in the next two days that he's ready to return after missing Week 14. Deandre Washington and Jalen Richard would once again handle the ...