Philadelphia demoted Rangel to Triple-A Lehigh Valley on Tuesday, Todd Zolecki of MLB.com reports.
Rangel was roughed up in his lone outing Monday since returning to the big-league club on August 9. The right-hander went 2.2 innings, allowing three runs on six hits and a walk while striking out three against St. Louis. The Phillies elevated Alex McFarlane to replace Rangel on the active roster.