2015 Dallas Cowboys training camp preview

The Dallas Cowboys open training camp July 30 at the River Ridge Residence Inn in Oxnard, California. Here’s a closer look at the Cowboys' camp, which wraps up on Aug. 28.

Top storyline: The Cowboys mostly ran their way to the NFC East title last season thanks to DeMarco Murray. He took his 392 carries and 1,845 yards to the Philadelphia Eagles in free agency. The runners looking to replace Murray -- Joseph Randle, Darren McFadden, Lance Dunbar and Ryan Williams -- combined for fewer yards last season than what Murray had in seven games. Though the Cowboys boast one of the best -- if not the best -- offensive lines in the NFL, the runner matters, as Jason Garrett is fond of saying. The Cowboys appear headed to a committee approach to replace Murray, but they would like one of the runners to become the leader of the committee. Randle will enter training camp with the job and showed flashes of ability on the field, but also flashes of immaturity off the field. The Cowboys want to keep the same formula that has been tried and true over the years -- run the ball, control the clock, ease the quarterback’s pressure to do everything and protect the defense -- but they need to figure out if they have a capable runner on their roster. If not, they will look far and wide over the summer at other teams to see if they can come up with an answer.

Position battles: The running back position battle was covered in the top storyline, and there aren’t many starting jobs up for grabs on a team that returns so many regulars from last season's 12-4 edition. The Cowboys lucked into grabbing La'el Collins as an undrafted free agent, and he will compete with Ronald Leary for the starting left guard spot. Unlike first-rounders Tyron Smith, Travis Frederick and Zack Martin, who were Day 1 starters, Collins will have to take the job away from Leary. Defensively, the suspension of Greg Hardy puts the defensive end spot up in the air for up to four games, with Jeremy Mincey, DeMarcus Lawrence and Randy Gregory battling for the two spots. The Cowboys have options at linebacker with only Sean Lee a lock. Rolando McClain looked to be a lock before his suspension, but now the middle and strongside linebacker spots could have competitions. Jasper Brinkley was signed before McClain and can be a solid run-stopper. Anthony Hitchens showed last season that he can be a playmaker at any of the three linebacker spots. Hitchens, Kyle Wilber and Keith Rivers will be in contention for the strongside spot.

Veterans to watch: Lee missed last season with a torn anterior cruciate ligament, leaving the Cowboys without their best defensive playmaker. He is completely healthy, but will be making a position switch to the weakside linebacker spot. The adjustment should not be a big deal, but the Cowboys need Lee to return to form and remain healthy if the defense is to make a significant jump in 2015. Hardy was the Cowboys' biggest free-agent signing, but he will miss four games because of a suspension. When he returns to the field, the Cowboys need Hardy to be a difference-maker, and Hardy needs to put up numbers to help secure his future. He is on a one-year deal, with eyes on gaining a huge contract if he can return to form and stay out of trouble.

Rookies to watch: Despite having only one first-round pick, the Cowboys secured three first-round talents in Byron Jones, Gregory and Collins. Of the three, Collins might have the best chance to start Week 1 if we use the traditional definition. Jones and Gregory will play key roles in the sub packages early if they don’t start. Jones showed in the spring he can play outside and inside at cornerback, and there could be some occasions when he lines up at safety. Gregory’s skill as a pass-rusher could transform the defense. If he can avoid the struggles many rookie pass-rushers face, the Cowboys will have a versatile front four that can change the way they play on the back end.

Bubble watch: McClain was the Cowboys’ most productive defender in 2014, but he put himself in this spot by violating the league’s substance abuse policy and landing a four-game suspension. There is no doubt he is skilled, but the Cowboys have more linebacker depth this year than they had last season. The Cowboys needed McClain last season and had to live with his uncertainties. With the addition of Brinkley, the potential of Hitchens and the possibility of moving Lee back to middle linebacker, if McClain does not show dedication this summer he could play his way off the roster.

Same game plan: Despite losing Murray and not making major additions at running back, Garrett and offensive coordinator Scott Linehan said the Cowboys will rely on the run just as much this year as they did last season. That is an easy thing to say before the pads come on, but a difficult thing to do with questions in the backfield. Given their ability to throw the ball with Tony Romo, Dez Bryant and Jason Witten, can Linehan be willing to stick with the run even if it is not producing the way it did in 2014? The formula worked so well last season, the Cowboys will be as patient as possible.

For daily updates at camp, check out the Dallas Cowboys clubhouse page.