Phillies' Aaron Nola on DL with elbow strain

PHILADELPHIA -- The Phillies have scratched right-hander Aaron Nola from his scheduled start Wednesday night and placed him on the 15-day disabled list with a strained elbow.

Right-hander Phil Klein, who is 0-1 with a 5.19 ERA in eight relief appearances for the Texas Rangers this season, will instead start against the San Francisco Giants.

Nola (6-9, 4.78) said he felt discomfort after his most recent start in Atlanta on Thursday, but he "really didn't think it was anything."

The 23-year-old has been struggling for nearly two months and has a 9.82 ERA in his last eight starts. The Phillies skipped him once in the rotation before the All-Star break, but Nola said his struggles have had nothing to do with his health.

Klein is 2-3 with a 4.80 ERA in 36 career games. The Phillies claimed him from Texas on June 19. He was 1-1 with a 2.13 ERA in eight games with Triple-A Lehigh Valley before being called up.