"At some point early last season, Felix Jones lost his identity. The qualities that made the Cowboys running back an attractive pro prospect — speed and elusiveness — had been buried under five pounds of muscle he added to his upper body. He wasn't as quick or nimble, and seemingly incapable of doing his best Barry Sanders impression.

After Jones attempted to increase his durability with a modest weight gain last off-season, he realized his best assets had been subtracted once the games began.

Having averaged 6.5 yards per rush attempt in his first two seasons, he produced only 4.3 yards per carry in 2010. A closer look would reveal why there was such a marked decline.

Only three of Jones' 185 carries — or 1.6 percent of his workload — resulted in a run of 20 yards or more. At first glance, those numbers seem scanty for a player billed as a game-breaker.

But they appear particularly meager when comparing them to his output in 2008, when he was a rookie playing a supporting role. Back then, Jones covered a distance of 20 yards or more on 10 percent of the 30 rush attempts he was afforded."