Parra had been sidelined since July 20 with a sprained left elbow. He's 1-1 with a 4.00 ERA in 24 relief appearances this season. He also was on the disabled list from April 29 to May 24 with a strained neck. With Parra out, closer Aroldis Chapman was the only left-hander in the Reds bullpen.
The Reds optioned outfielder Kyle Waldrop to Triple-A Louisville to open a roster spot. Waldrop was called up on Friday and batted once during a weekend series against Pittsburgh, striking out.
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