‘Spiller is entering the final year of his contract and is going to be 27 years old in August. Those two facts alone make his future in Buffalo beyond 2014 uncertain. Will the Bills be willing to pay Spiller what he wants as he inches closer to 30? He struggled through injuries last season and would need a fully healthy year to justify a big contract extension. In terms of cost, Spiller is going to require the biggest investment among the backs on the roster.’