Brett Anderson was diagnosed with a navicular stress fracture of his right foot and will be shut down for four weeks. Rough news for Anderson, who just can't seem to stay healthy. The 25-year-old southpaw is set to be reevaluated after four weeks, so his actual return to the Athletics likely won't be until around the early part of July. Dan Straily is filling his spot in the rotation for now, but the A's could turn to Sonny Gray if he continues to struggle.