At No. 18 in our 2012 NFL Mock Draft, the San Diego Chargers find themselves in need of a pass rusher—and most of the pass rushers, surprisingly, still available. The SB Nation mock draft has them selecting rapidly rising linebacker Shea McClellin, but I see them going with Alabama's versatile Courtney Upshaw, who began the mock draft season higher up on most boards than this.

If he's still available at 18th overall, I just can't see the Chargers passing; he's the right combination of best-player-available and drafting for need. And he could be quite a bargain for the Chargers, who would get the mountainous Upshaw at a slight discount—thanks to his poor workout season—and fill a need at the same time. Last year's Chargers had just one player—Antwan Barnes—with more than four sacks. Upshaw, who had 9.5 for Alabama last year, is a very good bet to top that in 2012.

SB Nation St. Louis's 2012 NFL Mock Draft is headed all the way from No. 1 to 32 leading up to Thursday's actual 2012 NFL Draft. You can follow along at our draft storystream, or read more mock draft recaps in our mock draft analysis storystream.

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