Jay Ratliff Dallas Cowboys
Cowboys tackle Jay Ratliff missed 10 games last season due to injury, and his health could determine how well the Dallas defense improves this coming season. Reuters

The Dallas Cowboys couldn’t run the ball and were near the bottom of the league in rushing defense. They also struggled to defend the pass, and still came within one game of making the playoffs for the first time since 2009.

All serve as examples of unfulfilled potential for a very talented roster that could challenge once again for the NFC East crown.

Dallas and head coach Jason Garrett opened up training camp on Saturday at City of Oxnard Fields in California, and according to the Dallas Morning News there was an air of “optimism.” Garrett, as well as owner Jerry Jones, believes the team can improve in every facet of the game, and they also commented on the health of recent $108 million quarterback Tony Romo.

Romo had a cyst removed from his back in April and did not participate in any of Dallas’s mini-camps or OTAs, as reported by Fort Worth Star-Telegram. The plan is to monitor Romo and his number of throws closely. The 33-year-old was third in the NFL in passing yards, sixth in passing touchdowns. He was also tied for first with 19 interceptions, but posted a career-high 648 pass attempts.

The top priorities for Dallas in training camp will be integrating new defensive coordinator Monte Kiffin's 4-3 schemes, and protecting Romo as well as providing him with more help on offense.

Below are five players to keep an eye on during training camp.

Sean Lee, LB

He appeared in only six games due to a toe injury, but made that time count with a combined 58 tackles. Lee will enter his fourth year in the NFL, and if winning isn’t a big enough motivator, the fact that he will be a free agent at the end of the season should be.

The Cowboys are in the midst of a switch back to the 4-3 defense under Kiffin, and a strong, smart inside linebacker is key to Kiffin’s system.

Travis Frederick, C

Coming out of running game powerhouse Wisconsin, he was one of the top rated offensive lineman in the draft, and from the get go he will be expected to contribute and drag the Cowboys running game from the doldrums of the league. Dallas ranked 31st in the league with 79.1 rushing yards per game.

Of the four centers on Dallas’s roster, two (Ryan Cook and Kevin Kowalski) are in contract years. How well Frederick performs could help the Cowboys save some cap space and avoid re-signing either.

There has been talk that he could move to guard, but either way he should play an integral role in running schemes.

Joseph Randle, RB

For a rookie itching to get into their first game, sitting behind DeMarco Murray on the depth chart might be the best chance for playing time in the NFL. Murray is reportedly healthy after suffering a foot injury last year, but Dallas should work him back slowly which means some early touches for Randle to prove himself.

Coming in at 6'0 and nearly 200 pounds, Randle has the size and speed to be effective right away. In three years at Oklahoma State, he averaged 5.4 yards a carry and had 40 career touchdowns.

Jay Ratliff, NT

Like Lee, Ratliff only appeared in six games and his failure to return from a back injury reportedly caused an argument with Jones in front of the team.

Apparently everything has been squashed, and the four-time Pro Bowler and 2009 All-Pro could be a huge cog in Kiffin’s new system. When healthy, Ratliff is one of the best in the game, and he will need a solid bounce-back year considering he represents the seventh highest cap hit on the team.

However, he was placed on the PUP list on Sunday with a hamstring injury attained during a conditioning run on the first day of camp, according to NFL.com. Ratliff may have to learn to play through some discomfort for the better of the team.

Will Allen, S

Overall Dallas had the 19th best pass defense in the league last year, allowing 230.2 yards in the air a game, and 52 plays of 20-plus yards. Signing 10-year veteran Allen (who helped Pittsburgh earn the best pass defense in the league last year) to a rather inexpensive one-year deal could be one of the biggest steals in free agency.

The 31-year-old could aid in the development of young corner Morris Claiborne, and help strong safety Barry Church prevent longer plays downfield.