AP

After a disappointing rookie year, the Chargers were hoping that 2010 top-15 pick Ryan Mathews would turn the corner this year and take hold of the primary running back job in San Diego.

Perhaps that will happen, but the kid is off to a rough start.

Mathews failed his conditioning test to start camp. Kevin Acee of the San Diego Union-Tribune writes that invited a lock of mocking and “some incredulity” by his teammates. His teammates describe the conditioning test as fairly easy.

“I haven’t been doing much speed work like that. There’s a couple things I probably should have done differently in the offseason, conditioning my legs,” Mathews said.

Once Mathews passed the test and got back on the field, he didn’t stay there for long. He’s missed the last few days of work due to “soreness” or a toe injury, depending which San Diego paper you read. Coach Norv Turner hopes Mathews returns in the next few days.

It’s one thing to see a defensive tackle struggle with conditioning, but it’s a little eye-opening when it happens to a running back. It’s a good thing the Chargers still have Mike Tolbert on the roster to share the load with Mathews.