Gaither will miss the Chargers opener with a back injury. (US Presswire)

Protection for Philip Rivers was a big issue for the Chargers in 2011. Mid-season (and twice-waived previously) acquisition Jared Gaither became the solution during the year and San Diego inked him to a four-year deal this offseason.

But as our Rapid Reporter Dan McLellan pointed out on Sunday, Gaither won't likely be healthy enough to start the opener because of back trouble. And that means that rookie and undrafted free agent Mike Harris will probably be tagged to protect Rivers blindside in the opener against the Raiders.

The former UCLA product was enthused about making the roster but also using the chance to show what he can do.

"I know Jared is down right now," Harris said via McLellan. “I know when he gets back the team is going to need him because he is a great tackle. I'm just taking what he is giving me. He's trying to help me every day because this is a team sport."

Bolts GM A.J. Smith, who also said that Gaither right now is "hurt and not available," echoed Harris' enthusiasm.

"Mike will get the first opportunity to hold down our left tackle position," Smith said, per the San Diego Union-Tribune. "He is a talented kid with a bunch of ability. He is excited about this opportunity, and we are all excited for him."

But Smith and Harris' excitement doesn't mean the Bolts are content here, and they shouldn't be. San Diego is continuing to explore their options for possible offensive-line additions, especially since, per the Trib, no timetable has been given for Gaither's return, and no one's ruled out -- gulp -- that he could miss the entire season.

That's a terrifying prospect for San Diego in a make-or-break year for Norv Turner.  It's precisely why the Chargers are out there hunting for depth at left tackle, and it's certainly enough to give pause when making prognostications about who will emerge from the scrum that is the AFC West.

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