Chargers running back Ryan Mathews has shown flashes of brilliance in his short NFL career, but injuries have kept him from reaching his full potential.
That trend continued Thursday night at Qualcomm Stadium.
Mathews suffered a broken clavicle on his first carry of the season against the Green Bay Packers.
The former first round pick -- who was supposed to be the heir apparent to LaDainian Tomlinson -- will have surgery on Friday and is expected to miss four to six weeks, which could have him back by the third game of the regular season.
Head coach Norv Turner is not ready to write off Mathews, who came into training camp in the best shape of his career.
"My hopes for Ryan have not changed," said Turner. "I hope he has a great year."
Turner also said the Chargers might keep up to five running backs on the roster.