The Chargers currently have 10 defensive linemen on the roster. Assuming that they retain 8 of them for the season, here is a summary of the personnel on this unit in reverse order of expected importance and production:
10: Cameron Botticelli
Height: 6-4, Weight: 290, Age: 23; Undrafted Rookie
A camp body that will probably be gone after the first round of cuts, unless there is an injury or he impresses the coaches in August much more than he impressed scouts in March. If he shows something, he can be placed on the practice squad.
9: Damion Square
Height: 6-2, Weight: 293, Age: 26; 2 years, 0 career starts (2013 UDFA, signed by Eagles)
Square has already been with two other teams, signing with the Eagles in 2013 and appearing in 10 games. He was released from Philly during camp last year, then KC kicked the tires for 6 games and released him. The Chargers picked him up in November and he was inactive for the remainder of 2014. He will need to make an impression in camp or he could join Botticelli with the first cuts. He is not eligible for the practice squad, so this may be the end of the line.
8: Darius Philon
Height: 6-1, Weight: 300, Age: 21; Rookie (2015 6th round by Chargers)
He will be given a good look in training camp, but he is not assured of making the roster (just ask Grice and Reese). Philon was a surprise early defection from college and has only two years of NCAA experience. He was productive in those years. His plusses are good speed and lateral movement, with a top-shelf initial burst and use of the hands. His drawbacks are a lack of elite power and needing to add some bulk and strength to shed blocks better. If he sees the field in 2015, it will probably be on third downs as a pass rusher. He is also practice squad eligible.
7: Tenny Palepoi
Height: 6-1, Weight: 298, Age: 24; 1 Year, 0 career starts (2014 UDFA, signed by Chargers)
BFTB writer Shane Theodore evaluated Palepoi last year, giving him a 15% shot of making the team. His athletic ability was unquestioned, but his drawbacks (like Philon's) were less than elite strength and power to play interior line and little experience at end. The coaches must have liked what they saw because he not only made the team, but he appeared in all 16 games as a rotational lineman. This is a player that I believe will be better this year, due to development, another year of conditioning, and adjusting to the NFL.
6: Ryan Carrethers
Height: 6-1, Weight: 333, Age: 24; 1 year, 1 career start (2014 5th round by Chargers)
With the classic height, weight, and frame of a Nose Tackle, Carrethers also brings freakish strength to the line. He appeared in just 6 games in his rookie season, before dislocating his elbow against the Raiders in Week 11 and not appearing in another 2014 game. Where Palepoi benefited from a year of work to get stronger, Carrethers has also benefited from having a year in which to improve his technique and learn about playing Nose in the NFL. If he learns how to apply his 00 strength to the field, he could easily become the Chargers' primary NT on first and second down.
5: Mitch Unrein
Height: 6-4, Weight: 306, Age: 28; 4 years, 3 career starts (2011 UDFA, signed by Broncos)
A player that was forced to crack the roster of both a college team and then the NFL the hard way, Unrein brings versatility and superb work ethic to the line. The consensus among Broncos fans was that they would have liked him back in Denver, but that he was replaceable. Unrein is a 5 technique DE in the 3-4 and he can slide inside when the Chargers show a 4 man look. He will probably press Reyes for starting duties and be a solid addition to the DE rotation on any down.
4: Ricardo Mathews
Height: 6-3, Weight: 300, Age 27; 5 years, 8 career starts (7th Round 2010 by Colts)
Mathews was a solid contributor in the DL rotation last year, even starting two games. He is effective at doing what a 3-4 lineman should be doing, occupying two blockers and being disruptive when single teamed. Mathews has shown incremental improvement since making the Colts roster in 2010. He was effective last year and there is no reason to think he has regressed. There is reason to think that he has improved with one more year in this system and the additional experience he got in 2014. He may push Reyes for starts or at least more frequent playing time on first and second downs.
3: Kendall Reyes
Height: 6-4, Weight: 300, Age: 25; 3 Years, 35 career starts (2nd Round 2012 by Chargers)
Reyes needs to regain the form he showed in his rookie and sophomore seasons. He was an effective pocket crusher, accumulating 10 sacks in his first two seasons. Last year, his production nosedived sharply. Despite starting 15 games, his tackles were around the level he had as a rookie, when he started just 4 games. He got blocked out too easily on rushing plays and was frequently MIA in the pass rush, getting only one sack. His last few games of 2014 seemed to show improvement (at least according to the eye test), but the entire line seemed to be playing better in the last 6 games of the season. He will be pushed for playing time this season, but will probably be given the chance to show that last season was an aberration.
2: Sean Lissemore
Height: 6-3, Weight: 303, Age: 27; 5 years, 16 career starts (7th Round 2010 by Cowboys)
Lissemore did not make many tackles last season, but he had only 29 opportunities to do so on run plays in his 8 starts and 15 games. What that tells me is that he was creating enough of a traffic jam for backs to go elsewhere or getting completely blocked out on too many plays. He did stop ball-carriers on 20 of those plays, which is acceptable. Like the rest of the line, it often looked like he was on roller skates early in 2014, but this had changed over the last 6 games of the year. His play overall was "good" last season, but certainly not game-changing. His production has been steady since 2012 and he is a good fit in the 3-4 defense run by the Chargers.
1: Corey Liuget
Height: 6-2, Weight: 300, Age: 25; 4 years, 61 career starts (1st Round 2011 by Chargers)
Liuget is soft spoken off the field, but on the field he is the best defensive lineman the Chargers have. Liuget is routinely double teamed and often still beats the blocking and alters the play or makes the tackle. At age 25, he has the most game experience of the linemen. The Chargers locked up his disruptive ability long term this offseason and he will be needed to continue to perform at the level we have all gotten used to seeing from him.
Among the 8 linemen expected to be on the roster when the Chargers try to tame the Lions in week 1, there are 124 total starts. Take away Liuget's experience and you are left with 7 players that have 63 starts. Further remove Reyes from that group and you have 6 linemen with 28 starts among them. That sounds like fairly slim pickings, but that only tells part of the story.
There will be just one rookie that may see time this year. All but Philon and Unrein have played football together under the same coaches for at least one year. Palepoi and Carrethers in particular got some experience last season and should get better this year. Add in Mathews' continued development (with his nice streak of nasty) and the addition of the versatile, hard-working Unrein and this unit should pick up where it left off at the end of 2014.
The unit held up its end of the deal in 3 of the last 4 games and even in the wild shootout in Santa Clara, the line forced a fumble and turned that into a defensive score. The defense held New England to 23 points and Denver to 22 points. The offense could not get it done in those games.
Telesco has put together a group here that has a diverse skill set. Palepoi, Reyes, and Philon are fast for their size, showing good lateral movement and decent straight line speed for 300 pound men. Mathews, Carrethers, Unrein, and Lissemore are mashers, not fast but tough and strong. Liuget has both power and agility. The personnel are well tailored for down and distance based situational groupings and even permit the Chargers D to play 4-man fronts with a credible rotation.
The gameplan seems to be an obvious inference: wrecking balls to control the line of scrimmage and keep the run game under control. When the offense has given the team the lead, put in the quicker and more agile guys to terrorize the QB. That plan did not work well last year, as the unit had inexperienced or banged up players on the field too often. Frequently, Pagano used defensive alignments with 2 down linemen. This is a recipe for disaster against the run or even against the pass, without fast blitzers coming from unpredictable angles.
This year should be different and better. One year older is a good thing for the players in this group. Telesco did not go out and get "better" players because he saw what we all did last season. The players on the 2014 roster were all becoming better players the more they played. This year they will start out better.