After hearing that your teams starting running back is out for an extended period of time you might worry, to have it happen twice in one season may even cause panic. However, for these Arizona Cardinals, who have had a lack of a running game all year, this could just be a gift yet to be opened.
The very fact that the Cardinals are one of the worst running teams in the league makes this really a non factor for the rest of their season, they could either average 3 yard per carry with Beanie Wells running, or they could average 3 yards per carry with their 4th stringer in the game. So really the only place their running game can go is up; so with this injury to Ryan Williams, it just means someone else will get a chance to do what Wells and Williams weren't able to.
It appears as if the next player in line is second year pro William Powell. The good news about Powell is that he has never been given a chance to be a teams workhorse, so this means he really has unlimited potential and if he plays like he did in the preseason he should be the long term starter. This preseason Powell appeared in every game and put up some unexpected numbers, on 42 carries he was able to have a 5.9 yards per carry average and found the end zone three times.
With more and more undrafted and overlooked running backs becoming important members of their team, it shouldn't be unexpected for the same thing to happen in Arizona. William Powell just may be in line to become the next star running back that was undrafted, all he needs to do is prove that this preseason was for real and not a fluke.