We could see a lot of changes coming in backfields across the NFL, especially after a number of performances in Week 4. DeMarco Murray tops the list of the league's best, as he leads all backs with 534 rush yards through the first four games of the season.

Perhaps Jerry Jones postponing contract talks with Murray has fueled the running back in the beginning of the season. The 26-year-old is still under his rookie contract and he also leads the league in attempts (99), rush yards per game (133.5), carries of 20-plus yards (5), and rushing touchdowns (5). Murray is building off of a successful 2013 campaign in which he rushed for 1,124 yards and scored 10 total touchdowns. Based on his performance at the end of his rookie deal, a contract extension could be headed his way.

"We're always open to extending good football players and guys who are leaders, and DeMarco is the type of person you want on this football team," said Jerry Jones' son, Stephen Jones, who is the COO of the Cowboys. "He's a smart guy, he's tough, he represents the team well. He's obviously playing at a high level right now. You like to keep good football players, and he's one of those guys."

But not too many others are seeing the success Murray is having. Carolina Panthers running back DeAngelo Williams sustained a high ankle sprain against the Baltimore Ravens on Sunday and is expected to miss a few weeks. Carolina's backfield is already decimated as Jonathan Stewart (knee) is expected to miss up to three more weeks and Mike Tolbert (leg) is out until Week 13. Williams was already battling a thigh injury, but now the ankle will keep him out of action for some time. With all of these injuries, undrafted rookie Darrin Reaves could get the start in Week 5.

The Chargers watched running backs Ryan Mathews and Danny Woodhead fall to injuries, so Donald Brown has been getting a bulk of the carries these past couple of weeks. But he's been miserable to say the least, carrying the ball a total of 50 times all season for just 100 yards, including 10 carries for 19 yards this past week against Jacksonville and 31 carries for 62 yards the week before against Buffalo. Mathews is expected to return within the next month, but don't be surprised if rookie Branden Oliver gets more touches in Week 5.

There's a similar situation in Minnesota with Matt Asiata and rookie Jerick McKinnon. With Adrian Peterson's suspension, the doors have opened for these two, but Asiata had his chances in Weeks 2 and 3, but failed to impress rushing the ball (25 carries for 71 yards). He managed to record eight receptions for 84 yards and a touchdown, but the Vikings need a true No. 1 running back. After Sunday's performance, could rookie Jerick McKinnon be that guy?

The rookie impressed against the Falcons with 18 carries for 135 yards along with one reception for 17 yards. Asiata had a decent game himself, carrying the ball 20 times for 78 yards and three touchdowns. But McKinnon's speed and versatility could begin to get him more carries in a Minnesota offense that is looking for answers now that Teddy Bridgewater is under center and Peterson is likely gone forever. And the fact that McKinnon is looking to improve in a multitude of ways could impress the coaching staff.

"I've been improving in pass protection and other things besides running the ball," he said, in this Minneapolis Star Tribune article. "I think I can develop into an all-down running back. That's something that I have my eyes set on."

Only time will tell for these backs, so stay on the lookout if you're in need of offensive help for your fantasy team.