Which Backup Running Backs are Primed for Success?

With injuries to Ty Montgomery, Chris Carson, Darren Sproles and Dalvin Cook, there is quite a bit of value to be had at the running back position. The problem is, it is hard to trust understudies Aaron Jones, J.D. McKissic, LeGarrette Blount/Wendell Smallwood and Latavius Murray.  Of these players thrust into a starting role, which one will you have the most exposure to in week 5? Include both cash game and GPP options.