Getty Former San Francisco 49ers and current Tennessee Titans DT Sebastian Joseph-Day The San Francisco 49ers need additional depth on the defensive line, and they could look to a former team member for help. San Francisco is 4-4 and dealing with a heap of injuries. With DT Javon Hargrave out for the year, Yetur Gross-Matos on the IR and Kevin Givens also dealing with an injury, Sporting News writer Vinnie Iyer is predicting the 49ers to make a trade for Tennessee Titans DT Sebastian Joseph-Day.