Dissecting San Diego Chargers' Best, Worst Positional Units

The San Diego Chargers' roster is far from perfect, as is the case with just about every other team gearing up for the 2015 season, but a select few positional units stand out as being either the best or worst.

Each positional unit on the current roster has been dissected and analyzed to distinguish which of these ranks as the best and worst on the team, and for the purposes of keeping things brief, I've narrowed it down to the best two and worst two. Overall ability of the group, along with age and experience, factored into the decision-making process, but so was how they stacked up against the entire roster.

And now for the results.

Best: Secondary

CB	SS	FS	CB
Brandon Flowers	Jahleel Addae	Eric Weddle	Jason Verrett
Chris Davis	Jimmy Wilson	Darrell Stuckey	Patrick Robinson
Steve Williams			Craig Mager

It seems like only yesterday the Chargers had one of the weakest secondaries in the league, but the arrival of Brandon Flowers and Jason Verrett sparked a turnaround in 2014. San Diego had the fourth-best passing defense last season, up 25 spots from 29th in 2013, and if this group can manage to stay healthy for all 16 games, it has the potential for yet another top-five finish.

Flowers missed two games with a concussion, and Verrett played in just six games before suffering a season-ending shoulder injury, but in the brief time they were on the field together, it had the makings of an exciting pairing. And let's not forget the contributions from the back line of the secondary made by All-Pro safety Eric Weddle, who deservedly so earned the No. 1 ranking among his peers in the BR NFL 1000. He was also recognized with the highest grade for a safety by Pro Football Focus (h/t Eric Williams of ESPN.com). 

The Chargers did happen to lose a starting member of the secondary this offseason in Marcus Gilchrist, but they hope to supplant him with third-year man Jahleel Addae and versatile free-agent pickup Jimmy Wilson, who logged 13 starts for the Miami Dolphins in 2014. Also worth mentioning is 2010 first-round pick Patrick Robinson, who had his share of ups and downs with the New Orleans Saints but may be able to rehabilitate his career with San Diego.

Rookie Craig Mager is one to watch as well, as many are wondering what prompted the Chargers to draft the Texas State product 83rd overall when scouts projected him as a fourth- or fifth-rounder at best.

Worst: Defensive Line

DE	DT	DE
Kendall Reyes	Sean Lissemore	Corey Liuget
Ricardo Mathews	Ryan Carrethers	Mitch Unrein
Darius Philon		Tenny Palepoi

As good as Corey Liuget may be on his own, it doesn't hide the fact that San Diego's defensive line is among the worst positional units on the roster. Kendall Reyes, whose stock was on the rise before last season, took a giant step back in 2014. It was almost as if he experienced a sophomore slump as a junior, and with the final year of his rookie contract looming after next season, Reyes needs to convince the Chargers brass he can be a foundational player to include in their long-term plans.

Meanwhile, the trade to bring Sean Lissemore from the Dallas Cowboys in 2013 has not paid dividends despite the affordable price tag of a seventh-round pick in the most recent draft. Second-year man Ryan Carrethers, who played well before his season was cut short by injury, will push Lissemore for more playing time.

Additions in the offseason for this group include former Denver Bronco Mitch Unrein and fifth-round talent Darius Philon, who is said to have "considerable upside as an athletic one-gap penetrator," according to Mark Dulgerian of NFL Network. But upside won't help the Chargers win now, and Liuget can only do so much to carry the defensive line.

John Reed-USA TODAY Sports

Best: Quarterback

Tough not to include Philip Rivers in the conversation for best positional unit on the roster since quarterback is such an important role for this club. The Chargers will only go as far as he takes them in 2015, and based on his efforts last season, he's more than capable of getting them back into the postseason. According to Pro Football Focus, Rivers posted the second-best grade against the blitz behind Andrew Luck with 16, and he owned a passer rating of 119.2. No. 17 also finished second in PFF's passing grades on third down.

And providing the backup for Rivers is 10-year veteran Kellen Clemens, who is fit to answer the call should anything happen to San Diego's six-time Pro Bowl quarterback. Clemens started nine games in place of Sam Bradford not too long ago, and he actually led the St. Louis Rams to a couple of wins in 2013.

Worst: Linebacker

OLB	ILB	ILB	OLB
Melvin Ingram	Donald Butler	Manti Te'o	Jeremiah Attaochu
Tourek Williams	Kavell Conner	Denzel Perryman	Cordarro Law
			Kyle Emanuel

It's not a lack of talent at linebacker that worries me, but a fear of the unknown with how little this group has played. Inside linebackers Donald Butler and Manti Te'o, while gifted, can't seem to stay healthy, and I believe Denzel Perryman was brought in for that reason. Even when Butler was making plays and stuffing the box score with tackles early on in his career, injuries always seemed to interfere. But with the physical presence of Perryman, there is reason to believe this group can get better.

Outside linebacker has the same issue with experience as fourth-year man Melvin Ingram is the eldest of his position. Following behind him are third-year pro Tourek Williams and last year's second-round pick Jeremiah Attaochu, who is expected to start opposite Ingram next season. The pairing of Ingram and Attaochu may be enticing to fans, but the reality is it's unproven. Ingram stands the best chance to impress, but like some of his peers, staying healthy has been a difficult task to accomplish.