Ryan Mathews' season took a turn for the worse in Thursday night's preseason opener against Green Bay.
Matthews, whom the San Diego Chargers were counting on to lead their rushing attack, will instead miss four to six weeks with a broken clavicle, according to the San Diego Union-Tribune.
Matthews played in 14 games last year, rushing for 1,091 yards. He played in 12 games as a rookie.
For the Chargers, it is back to the drawing board at the running back position for the time being with Ronnie Brown, Curtis Brinkley and Jackie Battle available on the roster.
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Terry McCormick covers the Titans for TitanInsider.com