3. DeMarco Murray, Philadelphia Eagles running back: Murray is the poster-child for the perils of building through free agency in the NFL. Chip Kelly conceded this summer that Murray's extraordinarily heavy 2014 workload was a valid concern going forward, but opted to hand him a five-year, $40 million contract regardless. An investment of that size can't be allowed to fail, even if it means re-tooling the offense to suit Murray's strengths after watching him get outplayed by Ryan Mathews and Darren Sproles early in the season. Murray is a power runner who struggles to move laterally. The Eagles should have realized he was a poor fit for their spread attack.