Right-hander Neftali Feliz has encountered a potentially season-ending obstacle in his attempt to return from an elbow ailment.

The Rangers on Sunday scratched Feliz from a scheduled injury-rehabilitation start with Triple-A Round Rock because of increased elbow soreness. Feliz is to be re-examined by team physician Dr. Keith Meister, who will consult with head athletic trainer Jamie Reed to determine the next step.

Feliz, who moved from closer to starter this season, has been on the disabled list since May 19 because of inflammation in the elbow. The Rangers had hoped to have him back within 10 days, but there is an increasing possibility Feliz will not pitch again season.