Chargers' Freeney addition creates more questions than answers

Dwight Freeney struggled in 2012, his first season as a 3-4 OLB. (Paul Sancya/AP) If the San Diego Chargers could find any silver lining in Melvin Ingram's

Dwight Freeney struggled in 2012, his first season as a 3-4 OLB. (Paul Sancya/AP)

If the San Diego Chargers could find any silver lining in Melvin Ingram's extremely unfortunate ACL tear, it was that two veteran pass rushers -- Dwight Freeney and John Abraham -- still sat unsigned on the free-agent market. The Chargers wasted little time snatching up the 33-year-old Freeney, who will take Ingram's spot at outside linebacker and provide a veteran voice to a relatively young defense.

But here's the rub: Not only do the Chargers have to show they can adjust their defense to get Freeney in his preferred 4-3 set, they also still have numerous holes elsewhere on the roster.

Freeney said all the right things last offseason when the Colts' new coaching staff transitioned to a 3-4 look. The results on the field never met expectations, though. After being hobbled by a high-ankle sprain early, Freeney finished the year with 5.0 sacks (his lowest total since registering 3.5 while missing seven games in 2007) and a career-low 12 tackles.

It was a bit of a lost season for the longtime Colt.

San Diego's challenge will be to get him back in a situation he is more comfortable with -- Freeney notched 102.5 sacks over 10 Indianapolis seasons playing defensive end in a 4-3. Does San Diego have the horses to be successful with a hybrid 3-4/4-3 defense?

Sliding to a 4-3 look with Freeney at DE might create other problems. The responsibilities of the three current starting linemen (Corey Liuget, Kendall Reyes and Cam Thomas) would be different, and San Diego would either have to adjust to a nickel package or fit its 3-4 linebacking pieces into a varied scheme. The latter choice could be difficult, since neither Manti Te'o nor Donald Butler really looks capable of playing outside and Jarret Johnson is more of a two-down player.

Which brings us to talking point No. 2 from above: The Chargers' lingering needs elsewhere. Freeney (or a player with similar pass-rush abilities) became a must-have after Ingram was lost for the season. However, San Diego has been less aggressive elsewhere on its roster, leaving question marks at ...

• Wide receiver: The Chargers are putting a lot of faith in third-round pick Keenan Allen (who's coming off a knee injury) and their underachieving lot from last season, which includes Malcom Floyd, Danario Alexander, Vincent Brown, Robert Meachem and Eddie Royal. While Philip Rivers continues to take most of the heat when this team falters, he had very little help in the passing game last season.

• Offensive line: Rookie D.J. Fluker should step in and start at right tackle, but does anyone in San Diego really feel comfortable with the remainder of this situation? If the season started today, the Chargers probably would line up the highly inconsistent King Dunlap at left tackle and journeyman Chad Rinehart at left guard -- reliable guard Louis Vasquez left in free agency and joined the rival Broncos.

The Chargers reportedly have been in the mix for free-agent tackle Max Starks, though nothing has come of that pursuit yet. Fluker was the only draft choice the Chargers made up front, focusing elsewhere for the final six rounds. That decision could backfire.

• Cornerback: Gone is the 2012 (and 2011 and 2010) starting duo of Antoine Cason and Quentin Jammer. For now, their replacements are Derek Cox, a free-agent signing who graded out as the 71st-best corner in football last season on Pro Football Focus; Shareece Wright, a 2011 third-round pick with zero career starts under his belt; 2013 fifth-rounder Steve Williams, who surprised just about everyone by declaring for the draft following his junior year; and Johnny Patrick, claimed off waivers from New Orleans.

Is that group stout enough to hold up against, for example, Denver's high-powered aerial attack?

• Running back:Ryan Mathews still has to prove that he's capable of staying healthy and being a No. 1 back. He has just two (fairly cheap) years left on his current contract, so time is running out in that quest. None of the backs behind him -- Danny Woodhead, Ronnie Brown or 2012 seventh-rounder Edwin Baker -- are guys that you'd want to base a game plan around, either.

• Depth on defense: Mentioned cornerback above, but the Chargers' D-line depth essentially boils down to ex-Packer Jarius Wynn and a group of undrafted free agents. There also are more uncertainties than the Chargers would like at linebacker, with 2009 bust Larry English, D.J. Smith, Tourek Williams and others.

The Chargers also converted Marcus Gilchrist from corner to safety, to provide Brandon Taylor with competition alongside Eric Weddle. One of those two has to step up in a big way.

San Diego ought to be thrilled that Freeney remained available after Ingram fell -- the former Colts star will be welcomed with open arms by the Chargers' players and fans. He might still have a couple of big seasons left in the tank, too.

Much of that depends, however, on how exactly San Diego is able to utilize him and, in turn, on how the rest of the Chargers adjust to multiple fronts on defense.