Minnesota Vikings: What if Adrian Peterson breaks down?

The Minnesota Vikings are once again counting on Adrian Peterson to be a huge part of their offense, but what will they do if the 31-year-old breaks down?

The Vikings are entering territory few teams in NFL history have dared to explore. This year, the Vikings will count on a 31-year-old running back to be not only their primary ball carrier but their overall #1 offensive weapon.

How many backs Peterson’s age have had this much responsibility placed on their shoulders? Emmitt Smith, Frank Gore and Fred Taylor leap to mind as recent examples of RBs who were still productive past their 30th birthdays, but none of those three men was asked to carry as much of the load as the Vikings will expect…