The easy answers are the offensive line, tight ends, playcaller and the running backs themselves. The hard answers came from first-year running backs coach Gary Brown, who noted after watching film of the 2012 season that there were too many home run hitters and not enough singles and doubles guys.
The running backs didn't go for just the 3- or 4-yard gains and instead tried to get big yards when they weren't there.
But there are some positives regarding the Cowboys' run game:
1. The running back. DeMarco Murray did rush for 663 yards last season, 29th in the NFL. However, he was sixth among running backs with 12 first-down runs. He also compiled a 66.7 conversion percentage on third down. Expect these numbers to increase if Murray remains healthy. He missed six games with a bruised foot last season.
2. The offensive line gets bigger. The Cowboys drafted Travis Frederick in the first round with the goal of getting bigger in the interior. Frederick was getting first-team reps at center during organized team activities the last three weeks and that's expected to continue when the veteran minicamp starts Tuesday. Frederick is the same height (6-foot-3) as last year's starter, Phil Costa, but he's heavier (317 pounds). Add guards Nate Livings (320 pounds) and Mackenzy Bernadeau (320 pounds), and you have a bigger interior, which should help with runs toward the middle.
3. Bill Callahan's influence. Starting right tackle Doug Free said another season with Callahan as the offensive line coach will benefit everyone. The linemen have a better understanding of Callahan's zone blocking scheme and all the techniques associated with it. There will also be no more guessing about Callahan's expectations. The offensive line coach put Bernadeau and Free on notice during the 2012 season. He had Free share his role with Jermey Parnell toward the end of the season. Bernadeau shared first-team reps in practice with Derrick Dockery in the middle of the season. If you don't play well, Callahan isn't afraid to move you out.