The Padres selected Ahmed's contract on Sunday.
Ahmed is back in the majors and will provide infield depth in the absence of Mason McCoy, who was placed on the 10-day injured list with back inflammation. While Ahmed has been in the San Diego organization since Sept. 1, he never made an appearance with a minor-league affiliate and was instead working at the team's complex in Arizona. He had hit .232/.271/.300 in 69 games between the Dodgers and Giants this season.