Clarke (hip) had a setback Friday in the midst of a minor-league rehab assignment and is returning to the Athletics to be evaluated, Martin Gallegos of MLB.com reports.
Clarke went 1-for-2 in his first rehab game Friday, but he was pulled before getting a third plate appearance. It was thought that the rookie outfielder was on the verge of being activated off the injured list, but it now seems he'll be out at least a bit longer. A clearer picture of Clarke's timeline moving forward could emerge after he is evaluated.