Miami Dolphins: 5 Most Crucial Training Camp Position Battles to Watch

You don't have to pay a lot of money to go to the movies to see all the summer blockbusters. You can get as much action by attending Miami Dolphins training camp in a couple of weeks and watching all the roster battles unfold.

There will be at least a handful of really good battles, too. Thanks to a slew of changes at multiple positions, the Dolphins have created a lot of competition on their roster, whether it's for starting spots or backup duties. 

And make no mistake about it: Those battles will be just as important further down the depth chart as they are at the top. 

So, which battles will be the most intriguing to watch down in Davie, Florida, in August?

5. Running Back

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Lamar Miller (26, above) is the most likely running back to start for the Dolphins in 2015, but that is not 100 percent certain.

There are battles at the top of the Dolphins' depth chart at running back, and there are battles at the bottom. Those competitions appear to be two completely separate things. 

The competition at the top is between Lamar Miller and Jay Ajayi. Miller was the bell cow in 2014 with 216 carries for 1,099 yards. Despite leading the team in carries, he never earned more than 20 carries in a game and has only done so once in his three-year career. James Walker of ESPN.com does not expect Miller's usage to change much in 2015. 

And why should he expect it to change? Miller's been the focal point of the running game, but his touches have still been held back by the likes of Daniel Thomas in the past. This year, the biggest threat to touches is Ajayi, and there's no reason to think that Ajayi couldn't seize the No. 1 role from Miller at some point in 2015—though probably not right away.

Ajayi is an every-down back, and though his long-term future is in question due to lingering issues following a torn ACL, Adam Caplan of ESPN says there are "no short-term concerns." 

Further down the depth chart, we get a deep competition from LaMichael James, Mike Gillislee and Damien Williams over the third and fourth spots on the depth chart.

The Dolphins have carried four running backs in the past, and if that's the case again, one of the three players will be on his way out of Miami. As we speak, that player looks to be Gillislee, who offers the least value on offense of all three and also doesn't have any special teams value.

4. Linebacker

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Chris McCain (58, right) will have a chance to start in the Dolphins defense in 2015.

If last year's lineup is any indication, Jelani Jenkins and Koa Misi will probably be two of the three starters at linebacker for the Dolphins in 2015. The third spot is still up for grabs.

Chris McCain is the early favorite to start at the strong-side linebacker spot, according to James Walker of ESPN.com, but Jordan Tripp also earned some reps with the first-team defense this spring and could be a dark-horse candidate to start. By the look of it, Jenkins, Misi, McCain and Tripp would appear to be locks for the roster.

Where the depth chart goes from there is anyone's guess. There are several undrafted rookies who will be competing for roster spots, including Neville Hewitt, Jeff Luc and Mike Hull. Veterans Spencer Paysinger and Kelvin Sheppard are also vying for playing time. 

Sheppard appears to be a natural backup to Misi. He is strictly a middle linebacker, as he doesn't have the speed or athleticism to play on the outside, but his special teams ability makes him a strong candidate to finish the summer on the final 53-man roster. 

The Dolphins could feasibly carry six linebackers into the season, but it would leave them thin at other positions. Hewitt, Luc, Hull and Paysinger will all battle it out for that potential sixth spot, with the winner being the player who displays the most special teams ability in addition to showing his fit on defense. 

3. Defensive Tackle

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Earl Mitchell (above) looks primed to be a full-time player for the first time in his career.

After signing a contract worth nearly $60 million guaranteed, Ndamukong Suh is a lock to be a starter at defensive tackle. Even after signing free agent C.J. Mosley and adding rookie Jordan Phillips through the draft, Armando Salguero of the Miami Herald reports that veteran Earl Mitchell will move from a backup role into a starting role at defensive tackle for the Dolphins this year.

That being said, if either Phillips or Mosley dominates practices, it will be hard to make a case for holding him back in favor of Mitchell. The five-year vet has not yet been a full-time player in his career—he maxed out at 553 snaps in 2013 with the Houston Texans and had 543 snaps for the Dolphins last year.

The Dolphins drafted Phillips in the second round, presumably because they have high hopes for him to develop into a starting-caliber player over the course of his career. The 6'5", 329-pound monster with 34 ¾-inch arms is much better when using his size and length to bull rush blockers into the backfield or move them to the side so he can make a tackle. 

Like Mitchell, Mosley has also been a career backup, though he has made a good career out of it. He played 50.4 percent of the snaps for the Detroit Lions as a backup to Suh in 2014 and 53.9 percent of the snaps in 2012. He would fit nicely into the rotation, as well.

But those four aren't the only defensive tackles trying to make the cut. Look for undrafted rookie Ellis McCarthy, third-year defensive tackle A.J. Francis and second-year defensive tackles Anthony Johnson and DeAndre Coleman. Those four will likely compete for one remaining spot, if such a spot exists.

2. Guard

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Dallas Thomas (63, middle) is in a make-or-break year and may need to prove he is capable of being a starter if he wants to keep his job.

At some positions, the Dolphins are deciding who will be the starters. At other positions, they are figuring out who will be the backups. At guard, though, the Dolphins have to decipher the entire depth chart. 

Dallas Thomas, Billy Turner and Jamil Douglas are the most likely candidates to finish training camp on the roster, with two of those three winning starting spots while the third wheel becomes a backup. 

Thomas may be entering "put-up-or-shut-up" territory this summer. It's his third year in the league after being drafted in the third round out of Tennessee. He was a project after moving from tackle (where he played in college) to guard.

Thomas yielded seven sacks last year when he lined up at tackle but none when he was a guard, according to Pro Football Focus, so the project may not be a failure after all. Thanks to his experience at both positions, Thomas may get to stick around regardless of whether he wins a starting job. 

Turner is in a similar boat to Thomas as a converted-tackle-to-guard project, but Turner is only entering his second year. The North Dakota State product played only 17 snaps in 2014, but according to Barry Jackson of the Miami Herald, the Dolphins have been expecting him to be a starter at right guard since as early as January. 

Douglas was drafted by the Dolphins in the fourth round in the 2015 NFL draft. Thanks to his skill set as an athletic lineman who can block on the move, he is close to a perfect fit for the Dolphins' zone-blocking scheme. He doesn't have the NFL experience that Turner and Thomas have, but Douglas may be the best option to start on the inside. 

Veteran lineman Jeff Linkenbach could also compete for a roster spot at guard, tackle or potentially both. If he lands on the roster as a backup, his versatility could be valuable to the squad. 

1. Cornerback

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Will Davis (29, left) and Jamar Taylor (22, middle) are among the cornerbacks competing for positioning on the depth chart this summer.

Brent Grimes is locked in as the Dolphins' No. 1 cornerback. Everything else on the depth chart is up for grabs.

Jamar Taylor has the inside track to start opposite Grimes, according to Barry Jackson of the Miami Herald, but that doesn't necessarily mean he'll finish training camp in the same place. There are several other cornerbacks who could make a push for a starting job, including Brice McCain, Zack Bowman and Will Davis, just to name a few.

Taylor was a second-round draft pick in 2013, so the Dolphins have a lot riding on his development. He has a tremendous physical skill set, as he showed at the 2013 NFL Scouting Combine (4.39-second 40-yard dash, 22 reps of a 225-pound bench press).

He hasn't been able to translate those physical gifts to the professional playing field, though, and according to Pro Football Focus, he yielded 37 completions on 53 throws into his coverage over the first two years of his career. 

Let's say that Taylor will finish training camp as the No. 2 cornerback. There are still a lot of battles for playing time between Brice McCain, Bowman, Davis and rookie Bobby McCain, all of whom could make a case as the top option in the slot.

Brice McCain has the most experience in that role, but his play has taken a turn for the worse in recent years. He allowed 84 completions on 128 passes thrown into his coverage from 2013 to 2014 (65.6 percent) with seven touchdowns and four picks, according to PFF. 

Davis is the dark horse, but the third-year pro was playing well last year before an ACL tear ended his campaign. If he can pick up where he left off, he could be a major factor in the defensive rotation.

Unless otherwise noted, all advanced statistics provided by Pro Football Focus.