Oakland Athletics left-hander Brett Anderson could miss up to six weeks after he was diagnosed with a stress fracture in his right foot.
Oakland's opening day starter was on a rehab assignment when he felt pain in his foot while running in the outfield, the team said Friday. Anderson, who came back from Tommy John surgery last year, has been on the disabled list since May 1 with a sprained right ankle.
He is 1-4 with a 6.21 ERA in six appearances, including five starts. Anderson also pitched in relief during a 19-inning marathon on April 29, a game he was originally slated to start before being scratched.