Wheeler (back) won't make his scheduled start Sunday against the Athletics, Todd Zolecki of MLB.com reports.
The 34-year-old had an MRI on his back come back negative after he experienced lower-back tightness during Tuesday's start, but Philadelphia will play it safe and skip the right-hander's final outing before the All-Star break. Wheeler is expected to be ready to go to begin the second half, though it's unclear whether he'll be tabbed to start during the opening series in Pittsburgh next weekend.