After two weeks of preseason games, player roles are starting to become more clear and rankings are being shuffled as a result. We've had a chance to see how some new faces look in new places, who is out of shape and what players are being nagged by injuries. Today we breakdown the top-10 highest risers among running backs in Yahoo (standard) and NFFC (PPR) drafts.

Lamar Miller is a big winner in all formats due to Knowshon Moreno's absence from training camp with a knee injury. Word from Dolphins camp early on was that Moreno was out of shape to begin with, but he has now been cleared to practice and could still push Miller for the starting job. The Miami backfield hasn't exactly been a fantasy juggernaut in recent years, so even though Miller is No. 1 on the depth chart for now, fantasy owners may want to take a step back from this situation until the dust settles.

Toby Gerhart has been a fantasy darling since making the jump to Jacksonville and out from under the shadow of Adrian Peterson. There is really nothing different about the Jaguars backfield other than Gerhart has finally carried the rock in game action. His 19 rushing yards on six carries versus the Bears last week must have been enough to move the needle even further. At a lofty 44.3 ADP in Yahoo drafts, fantasy owners are banking on Gerhart being able to carry the load for the first time since leaving Stanford five years ago.

Speaking of paying for projection, Andre Ellington continues to climb fantasy rankings. The second-year back is dynamic and the definitive starter in Arizona, but we still haven't seen how well he handles every down duties in the NFL. There is almost no upside to Ellington at a 26.4 ADP.

It's a little surprising to see Trent Richardson's name as a riser. The one thing fantasy owners wanted to see was if Richardson looked quicker and more confident in Indy's backfield during the preseason. He has not. Ahmad Bradshaw is still out of the lineup, so Richardson doesn't have anybody pushing him for playing time, but that could change if he continues to gain less than three yards per carry. Still, drafting a full-time starting running back just inside the top-100 is not a bad price.

NFFC drafts have been less excited about rookies than Yahoo leagues all preseason long, but things are starting to change now that the first-year players have taken the field and teams have given a glimpse of how they will be utilized. Half of the top-10 NFFC risers are rookies, starting with Devonta Freeman of the Falcons. The 5-foot-8, 205-pounder, whose Yahoo ADP is also climbing,  has been flashing explosive ability as both a runner and pass catcher while making the most of extra carries with aging starter Steven Jackson nursing a hammy. It's only a matter of time before Freeman overtakes inferior runners Jaquizz Rodgers and Antone Smith as Atlanta's No. 2 back.

Carlos Hyde is the second rookie to make an appearance on both lists. He is a complete back and has already locked down the backup job in San Francisco behind Frank Gore. It's easy to get fired up about Hyde's potential in the 49ers power running game, but big numbers might be a year away. Gore's backup in 2013, Kendall Hunter, carried the ball only 78 times. Hyde, however, is dynasty gold.

Like Hyde, Terrence West and Jeremy Hill are handcuffs with secondary roles on offense that won't be heavy fantasy contributors unless a starter is lost to injury. Bishop Sankey has the best chance to start out of the gate, but is still behind Shonn Greene and Dexter McCluster on the Titans depth chart.