Chris Owings on DL due to shoulder
Arizona also transferred third baseman Eric Chavez to the 60-day disabled list with a sprained left knee.
Owings is batting .277 with six homers and 21 RBIs in 72 games, including 61 at shortstop.
Ahmed will be making his first appearance in the majors after hitting .324 with two homers and 36 RBIs in 79 games with Reno. He was acquired with infielder Martin Prado in a 2013 trade that sent outfielder Justin Upton to Atlanta.
Chavez has been on disabled list since June 9.
Arizona made the moves before Sunday's game at San Diego.
Copyright 2014 by The Associated Press
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