Before DeMarco Murray had even started one NFL game, he owned the Cowboys’ single-game rushing record.

Needless to say, Murray knows a little bit about fast starts -- not only to a game; in the Cowboys' sixth game last year, he took his first handoff and went 91 yards for a touchdown against the Rams -- but also for a career. Murray had a nice rookie year in 2011, but it was cut short by a broken ankle that wiped out the final month of the season. That could have been the very reason the Cowboys went from the NFC East leaders to out of the playoffs.

But now Murray is focused on building on his rookie season, stating that he’s even hungrier to prove himself this year.

“I think we always have something to prove,” Murray said. “You could be in your 10th season and you’ve got to show them you’ve still got it. If you’re a young guy, you have to show you’re for real. I’m still trying to get better. I have a long way to go. I am still trying to work hard and get the plays down, the blocking assignments down, but I am heading in the right direction. ... The sky’s the limit, and I'm excited to see how I do this year."

And the Cowboys are excited to see how he does, too.

Murray didn’t technically start the Rams game in late October, but he certainly carried the load, rushing for a Cowboys’ record 253 yards, breaking Emmitt Smith’s mark of 237 set in 1993.

Murray finished the season with 897 yards and a 5.5 average.

As he enters this season, it’s clear he will be the starting tailback -- ahead of Felix Jones. Murray provides more of a complete skills package, with the ability to be a home-run hitter but also pick up tough yards inside.

But what coach Jason Garrett said he likes most about Murray is the professionalism he exudes, especially for a second-year player.

“He just has a mature demeanor about him," Garrett said. “I think that's what allowed him to transition as easily as he did last year. I think the other thing is he's a mature player from a technical standpoint. You can tell he's a good runner. He has good vision.

“But then you ask him to run a route out of the backfield maybe that he hasn't run before, and he understands what you're asking him to do as a coach very quickly, and then he does it. From a pass-protection standpoint, it's the same thing. He hasn't had a tremendous amount of experience doing a lot of these different things, but he has kind of an instinct, an intuition, that the really good players have."

Whether Murray is really good or even on his way to greatness remains to be seen. But there’s no doubt in his mind that he will be doing everything possible to achieve those levels.

“I’m not going to be outworked, that’s the mindset,” Murray said. “As a professional, your job is to get ready to play at all times. I never want anyone to tell me to work harder. So I do that on my own. Hopefully it will pay off.”

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