The Dallas Cowboys' dynamic aerial attack in 2014, led by Tony Romo, Dez Bryant and Jason Witten, was a huge factor, but there's no doubt about it; DeMarco Murray set the tone.

Murray had a huge season last year, rushing for 1,845 yards, breaking Emmitt Smith's franchise record. He also tied with Seattle Seahawks back Marshawn Lynch for the league lead in touchdowns. Having said that, Murray is now in the City of Brotherly Love under Chip Kelly.

Can the Cowboys survive without Murray? Time will tell.

Joseph Randle, just 23 years old, has potential having averaged 6.7 yards per carry last season, but he obviously wasn't an every down back. Randle has great speed, and he's a smart back who knows how to follow his blockers. The Cowboys signed Darren McFadden this offseason, but injuries are always a concern with him.

McFadden has only once played all 16 games in a single season in his seven year career with the Oakland Raiders. Many NFL experts have gone far enough to label McFadden a "draft bust" given the fact that he was selected No. 4 overall, and he has only rushed for 750 yards in a season one time. Not only is health an ongoing concern, but McFadden has averaged a mediocre 3.3, 3.3 and 3.4 yards per carry the last three consecutive seasons.

So, should the Cowboys test the open market?

It may be late June, but a few notable free agent running backs are still available. Notable backs such as Steven Jackson, Knowshon Moreno and Chris Johnson are still free agents.

Jackson would be a great fit with the Cowboys behind that powerful offensive line. He produced 707 rushing yards last season on a terrible 6-10 Atlanta Falcons squad. McFadden on the other hand had just over 500 rushing yards and two touchdowns last season. Releasing McFadden wouldn't be very detrimental at all because only $200,000 of his contract is guaranteed money.

Jackson may be older than McFadden, but he's more productive and he stays on the field far more often. McFadden is currently battling a hamstring injury, and the preseason hasn't even started yet. Jackson certainly won't be leading the league in rushing yards next year, but he's more reliable and a better complementary back to play alongside Randle.

Johnson is also a free agent. Johnson has rushed for over 1,000 yards in six of his seven seasons in the NFL. He has also been very outspoken about playing for the Cowboys in the past. Johnson would be a good addition because he hasn't missed a game since his rookie year of 2008, has great speed, and he can break the big play at any given moment. He also averaged 4.3 yards per carry last year with the New York Jets, a yard more per carry than McFadden. The downside here is Johnson has his off-the-field issues and he does lack consistency.

Another option for the Cowboys is to bring in Moreno for a workout. Moreno is a very talented running back who helped the Denver Broncos get to the Super Bowl two seasons ago with his 1,038 yards and 10 touchdowns. Sadly, he tore his ACL last season with the Miami Dolphins, so health is a concern. If the Cowboys were to sign Moreno, it wouldn't be for long-term or a large amount.

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