Michael Harris was an unexpected surprise for the San Diego Chargers in 2012. He rose from being an undrafted free agent out of UCLA to the team's starting left tackle, thanks to a shaky offensive line. However, things aren't quite so sunny in 2013; Harris finds himself fighting for the backup right tackle job, according to UT San Diego.

While Harris' rise was impressive -- he started nine games last year -- his on-field play wasn't. In their preview for team needs, Pro Football Focus gave him a rating of -43.4, the lowest of any offensive tackle charted. This weighed heavily into the Chargers' decision to invest a first-round pick in Alabama offensive tackle D.J. Fluker.

More: More on the Chargers at Bolts from the Blue

The left tackle spot will be held by free agent Max Starks, signed this year, while Fluker will get the nod on the right. This leaves the backup RT spot as an open competition. San Diego has multiple players who can swing between both tackles, which makes the prospect of projecting the backup spots less than ideal.

Harris was largely a victim of circumstance last year, being asked to play left tackle as an undrafted free agent, and could still find himself as an important rotational player on the line.

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