Los Angeles Chargers safety Derwin James was diagnosed with a stress fracture of the fifth metatarsal in his right foot and “he will continue to be evaluated,” the team announced Friday afternoon.

James has a gray walking boot on his lower right leg after suffering the mishap on Thursday. The injury is on the bone on the outside of his foot, connecting to the bone of the pinky toe.

Ian Rapoport of NFL Network tweeted on Friday that James “will be out a significant amount of time” but the exact timeline and nature of the injury is unknown.

The 17th pick in last year’s draft, James was a first-team All-Pro and Pro Bowler, starting every game for the Chargers.

Los Angeles has already been without standout left tackle Russell Okung, who is recovering from a pulmonary embolism suffered in June, running back Melvin Gordon, who is holding out in pursuit of a contract extension, and receiver Keenan Allen, who may miss the rest of the preseason with an ankle injury.

James is a key piece of the Chargers’ defense, which is expected to be one of the best in the NFL this season.

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