Alvarez (shoulder) was pulled an inning early in his rehab start because of shoulder soreness, Connor Letourneau of the San Francisco Chronicle reports.
Alvarez, who received surgery last July to repair a torn right labrum, experienced what A's manager Bob Melvin called "a setback." It's troubling news for the 26-year-old, as he's been rehabbing his shoulder for more than nine months now and was nearing a major league return until Sunday's complication. More news concerning the severity of his setback will be released in the coming days, but either way, he's likely headed for an even longer rehab stay.