PHOENIX -- After sending down left-handed reliever Zac Curtis following Tuesday's loss to the Dodgers, the D-backs replaced him with lefty Andrew Chafin, who was recalled from Triple-A Reno on Wednesday morning.
Chafin struggled early this season before being sent down to the Minors to work out his issues. The 25-year-old left-hander was 0-1 with a 9.00 ERA, allowing 17 earned runs in 17 innings. In Triple-A, Chafin went 1-0 and allowed no runs in 7 2/3 innings. Chafin entered Wednesday's 3-2 loss to the Dodgers, pitching a perfect eighth inning.
"One of the biggest things was executing pitches," Chafin said. "I threw my changeup a good bit down there, and I feel comfortable throwing it in any situation now. It was more or less like a reset button, so to speak, cleared my mind of things and got back to the basics."
Last season, Chafin was one of the D-backs' most reliable relievers. He went 5-1 with a 2.76 ERA in 66 appearances. He is now the only left-hander in Arizona's bullpen.
Curtis, 23, was recalled from Class A Advanced Visalia on April 30. He began his Major League career with 8 1/3 scoreless innings in his first 10 appearances.

However, Curtis struggled in June. He had a 27.00 ERA in four appearances this month, allowing six runs over two innings.
"We felt like it was time for Zac to go back down and get some more work and get his breaking ball tightened up," D-backs manager Chip Hale said. "It hasn't been where we want it to be or where he wants it to be, so he needs the consistent work of development."
Curtis was sent down to Double-A Mobile. He had never pitched higher than Class A Advanced before he was called up to the Majors.