Nick Eatman

FRISCO, TexasThe Cowboys have added nearly 30 new players to the roster over the last two months, from a collection of free-agent signings, draft picks, undrafted free agents and even a few trades.

All in all, a third of the 90-man roster has been overhauled since mid-March, creating quite a few changes to each position.

Over the next few weeks, we'll take a closer look at where things stand at each position. The Cowboys won't release a depth chart until the first preseason game in August, so the following order of players is simply a projection, which of course, is always subject to change. Let's start the series with the running back position:

• Miles Sanders
• Javonte Williams
• Deuce Vaughn
• Jaydon Blue
• Phil Mafah
• Hunter Luepke (FB)

Battle to Watch:All of them, to be honest. There's nothing set at this position other than possibly Blue's spot on the roster. Even at that, he's a fifth-round pick and nothing is guaranteed. But the Cowboys haven't promised any of these players a spot on the team, much less a starting spot. So from a veteran standpoint, Sanders and Williams both have the experience and should get the chance to compete at the top. Needless to say, new RB coach Derrick Foster will plenty to work with in his first season leading this group.

Time is Now:This one has to go to Deuce Vaughn. No longer just the feel-good story of a player trying to find his niche in the NFL, Vaughn is entering his third season and has yet to make a major impact. Now the Cowboys have drafted two players who most likely will get plenty of carries in the preseason. So Vaughn has to show he is ready to take that next step. A good thing for him is reuniting with O-line coach Conor Riley, who was Vaughn's offensive coordinator at Kansas State.

Trait-Mark:At running back, there are a lot of traits that make up a great runner, but one the Cowboys were obviously looking for this offseason was speed. And when it came to the NFL Draft, Jaydon Blue had more speed than just about anyone. His 4.38 time was the second-fastest 40-time of any running back in the draft. He gives the Cowboys a speed-element at running back they haven't had since Tony Pollard, and even he didn't possess the track-speed quality they have now with Blue.

Don't Forget AboutWhile the Cowboys are looking to re-establish the running game, they probably will ask these guys to catch the ball as well. Both Sanders and Williams have caught 50 passes in a season with other teams, and Blue was electric out of the backfield for Texas, catching two touchdown passes in the College Football Playoff semifinals. The Cowboys are looking for more than just "runners" in the running back room.