Preseason will be more about determining if new faces can fix last year’s problems than fighting for roster spots. There are 18 new veteran free agents currently in camp and the first three picks of this year’s draft class appear ready to contribute. Now it is time to see if these new faces are the cure for last season’s ailments.

Three lingering questions:

Will the D-line be able to pressure the QB? The Chargers defense recorded just 32 sacks last season, 23rd worst (tied with Browns). General manager A.J. Smith identified improving the pass rush as his chief offseason concern. OLB Melvin Ingram (18th overall pick) was selected in the first round, followed by DE Kendall Reyes (second round, 49th overall pick).  OLB Shaun Phillips, a Pro Bowler in 2010 and OLB Larry English (first round, 2009) have recovered from feet injuries that kept them out of combined 13 games last season. Coach Norv Turner’s plan is to rotate DEs and OLBs for fresh legs and a consistent pass rush.

Can the defense get off the field on third down? The defense allowed opponents to convert 49.2 percent of third downs in 2011. How bad was it? It was the most inept third down defense of any NFL team since 1995 and the worst in franchise history since 1975 when opposing offenses converted 50.7 percent.

Improving the third down defense is directly connected to an improved pass rush, but other steps have been taken. OLB Jarred Johnson (free agent, Ravens) has only had a combined 4.0 sacks over the last two seasons, but is excellent at shutting down rushers. San Diego also hopes they are improved at SS with the additions of Atari Bigby (free agent, Seattle) and Brandon Taylor (round three, 7 rd overall pick).

Will the offensive line hold up? The O-line was in shambles for most of 2011 with several injuries including Pro Bowlers LG Kris Dielman (concussion) and LT Marcus McNeill (neck). QB Philip Rivers was sacked 28 times and threw 17 INTs through the first 12 weeks of the season. In Week 13, LT Jared Gaither (released from Chiefs) was signed and LG Tyronne Green (broken finger) returned to action. Rivers was only sacked two times and threw just three INTs for the remainder of the season. Dielman (retired and released) and McNeill (released) are no longer on the team.

Gaither was resigned in the offseason and the plan was to go with the same starting O-line that finished 2011. Gaither, however, has missed most of training camp with back spasms and returning backup G-T Brandyn Dombrowski (foot, cyst) has yet to practice. LT Mike Harris (undrafted, UCLA) has seen the baulk of the starts with the first-team and preseason will be a test for him.

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