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After Week 1 of the NFL season, we'll tell you not to read too much into it.

"It's just one game," we'll shout, stressing patience and prudence no matter the result.

And that is great advice, to be sure. Fantasy football is a game that demands at least some level of overreaction on a weekly basis; there are only so many chances for a player to turn things around in a 16-game season. However, how many times have we seen players put together huge Week 1 performances only to fizzle out beyond that?

Still, though you shouldn't change your opinion on a player solely based on Week 1, momentum built this early in the season can be tough to stop. Especially when it comes to running back battles, where two players might be separated by the thinnest of margins coming into the season anyways. Just last season, Justin Forsett came into the season expected to come off the bench behind Bernard Pierce, but his 70 yards and a touchdown performance in Week 1 ended up being an early sign of his excellent season to come.

We've tracked running back battles all training camp and preseason long, and this week is our first opportunity to see them officially battle. Who has the most to gain -- and lose -- in Week 1?

Dallas Cowboys

This one might take a while to sort out, especially with Joseph Randle failing to really run away with the job in the preseason. However, with the NFL's defending rushing leader departing for Philadelphia, the opportunity for a Fantasy star to emerge from this backfield is hard to ignore. The Cowboys boast arguably the best offensive line in the league, and that line helped Randle average a robust 6.7 yards per carry on 51 attempts last season.

Randle is expected to open the season as the starter in Dallas, and if he comes out of the gate strong against the Giants, it is entirely possible he puts the competition to bed early. The Giants ranked 27th in the league in rushing DVOA per FootballOutsiders.com last season, and DeMarco Murray rushed for 249 yards in two games against them last season, so Randle has a great opportunity ahead of him to open the season.

Of course, the Cowboys were so seemingly unenthused about Randle's prospects as a No. 1 option they brought in Darren McFadden in the offseason and traded for Christine Michael just days before the season to give themselves options. McFadden has the more extensive track record of the two, but it is mostly an unimpressive track record. He hasn't averaged more than 4.0 yards per carry since 2011, and has missed 29 of 112 games in his seven-year NFL career. Playing for the Raiders could explain away his uninspiring numbers, but at this point McFadden is enough of a known quantity to say he hasn't earned the benefit of the doubt.

The more interesting of the backup plans is clearly Michael, a combine star who found himself buried behind Marshawn Lynch in two seasons in Seattle. He impressed in limited opportunities in Seattle, however, and that came after a collegiate career in which he averaged 5.3 yards per carry and 69.8 yards per game at Texas A&M. He battled his own injury issues in college and hasn't had more than 150 carries in a season since his freshman year in college, but he might have the most upside of anyone in this trio.

It might take both Randle and McFadden faltering since he got such a late start with the team, but Michael's path to playing time could open up quickly if both stumble in Week 1.

Atlanta Falcons

Devonta Freeman's hamstring isn't much of an issue at this point, as he told reporters he is at "90 percent" Tuesday. However, that injury might have cost him his Fantasy appeal, as his lack of participation in training camp and preseason allowed rookie Tevin Coleman to take the starting job from him. Falcons coach Dan Quinn told reporters Tuesday Coleman will start in Week 1 against the Eagles. Whether Coleman can run away with the job remains to be seen.

The Falcons are likely planning to split work pretty evenly between their two green runners, so don't be surprised if Freeman ends up butting his way back into the conversation. However, Coleman has a terrific opportunity here, even with a tough Eagles' rush defense on the schedule to open the season. If he comes out and shows the skills that made him a 2,000-yard runner in Indiana last season, it might be tough for the Falcons to go away from him. And running the ball for this Falcons' offense could be a very lucrative opportunity, because there could be a ton of goal-line chances here.

If Coleman can't run away with it early and allows Freeman to get healthy, this one could be a headache for Fantasy players all season.

Cleveland Browns

Through five games last season, Browns running backs Isaiah Crowell, Ben Tate and Terrance West averaged 5.06 yards per carry between them, while racking up 143 yards per game on the ground. And then Alex Mack, their All-NFL center went down with an injury, and things completely fell apart. The trio averaged just 3.26 yards per carry overall from Week 6 on, with Crowell coming out looking best out of the three but still managing just 3.74 yards per carry.

The Browns rebuilt their running back corps since, waiving Ben Tate last November, trading West at the end of the preseason and drafting University of Miami back Duke Johnson in the third round of last June's draft. The return of Mack should be the biggest boon for their running game, and Crowell could be in line to take full advantage of it, especially with Johnson entering the season still dealing with the effects of a preseason concussion. If the Browns offensive line returns to form early in the season, Crowell could emerge as a Fantasy star in Johnson's absence.  

St. Louis Rams

With top pick Todd Gurley looming as a potential Fantasy monster, Tre Mason may not get many opportunities to establish himself as a relevant Fantasy option. If he stumbles even a little bit once Gurley is healthy, he probably won't get a second chance to prove himself, so the first few weeks of the season will be absolutely key.

The good news is, Gurley is out for at least Week 1 as he continues to work his way back from a torn ACL. The bad news is, Mason is dealing with a hamstring injury of his own, so his own availability is at least somewhat in question. If Mason is forced to sit, Benny Cunningham would get the start for the Rams in Week 1 against the Seahawks, which leaves exactly nobody excited. In fairness, that might actually not be a bad outcome for Mason, who is unlikely to impress much with the Seahawks on the schedule.

Still, Mason showed enough upside as a rookie, rushing for 765 yards in 12 games, that writing him off just because Gurley is lurking isn't fair. With the Redskins and Steelers on the way the following two weeks and Gurley without a timetable, there might be value in remaining patient on Mason, who could play well enough to give the Rams flexibility with Gurley's timetable.

Detroit Lions

Coming off offseason surgeries on his knee and Achilles, Joique Bell comes into the season with plenty of question marks surrounding him as a Fantasy option. He also comes into the season as the No. 1 running back on the team's depth chart for Week 1, and like everyone else on this list he has to hit the ground running. Because Ameer Abdullah has already been nipping at his heels. Heck, if you ask Fantasy owners, Abdullah has already nearly overtaken him, with an average draft position just a round later than Bell's.

This situation isn't as desperate for Bell as some of the others might be, because the Lions aren't one of those teams that invests in one running back too heavily. Three different backs saw at least 15 percent of the team's snaps last season, with Bell the only one topping 50 percent. And the year before, with both Bell and Reggie Bush healthy, they split playing time nearly evenly; if Bell and Abdullah both prove worthy, they'll both see the field, it's as simple as that.

Still, if Bell has lost a step, we might know pretty early on. And with a potentially explosive backup behind him, Bell might not get much of a benefit of the doubt here.