Montas will see his next scheduled start bumped back to Monday, Ben Weinrib of MLB.com reports.
The Athletics will activate Brett Anderson (shoulder) off the disabled list to start Sunday's game. That bumps Montas' next scheduled start to Monday's series opener against the Astros, when he'll look to bounce back from allowing nine earned runs on 17 hits and three walks across 8.2 innings over his prior two outings.