Some questioned the Dallas Cowboys' strategy of investing three first-round picks into their offense line, but that strategy paid off with a 12-4 season last year. Behind the NFL's best O-line, running back DeMarco Murray led the league in rushing with 1,845 yards on the ground and the Cowboys made the playoffs. But after totaling nearly 500 touches (including postseason), the Cowboys were right not to break the bank for Murray in free agency this year. However, maybe the team should have invested something into the running back position.

Dallas narrowly escaped with a victory over the New York Giants Sunday night with an average rushing attack. But now that star wide receiver Dez Bryant is out for an extended period of time following foot surgery, Dallas' running game will once again have to be one of the best in the league if the Cowboys hope to make the playoffs again.

"With him on the shelf, Dallas' running backs should become accustomed to seeing more bodies closer to the line of scrimmage, which will force these runners to make more one-on-one tackling matchups miss," ESPN NFL Insider Matt Williamson wrote. "I have my doubts this stable of backs can excel under such circumstances, even with the elite blocking they receive."

In 2014, Dallas led the league in time of possession (32:51) thanks to a slow-paced offensive attack that took pressure off the team's defense. That will be harder to do with Joseph Randle, Darren McFadden and Lance Dunbar as the top three backs. Randle, the presumed starter heading into this season, hasn't made much of an impression on Williamson thus far.

"Joseph Randle's numbers were more impressive than McFadden's, but I don't see workhorse qualities and he isn't a tackle-breaking runner," wrote Williamson. "Randle is not thickly built and really has little history of being a true bell-cow back. And to quote Dallas' lead back, Randle left too much 'meat on the bone' Sunday night considering the blocking supplied to him. In games that he has received double-digit touches during his career, Randle's numbers are well below average, which is putting it kindly."

McFadden has failed to crack 4.0 yards per carry over the last three seasons, and while Dunbar had a solid game, he's not a true feature running back. Similarly, Christine Michael, whom Dallas traded for last week, failed to gain any traction as Marshawn Lynch's backup in Seattle. All told, the Dallas backfield still hasn't answered many of the questions that dogged it during the offseason.

The Cowboys still have a healthy Tony Romo under center which should keep them in most games. But this team could be drastically different on offense without Dez Bryant and DeMarco Murray.