Demel, who was acquired by Arizona from the Oakland Athletics for Conor Jackson, made 72 relief appearances with the Diamondbacks. He posted a 4.95 ERA over 63-2/3-innings with Arizona while also recording two saves. He spent the majority of the 2012 season with Triple-A Reno, making just one appearance with Arizona.
The 25-year-old Elmore made his Major League debut with the Diamondbacks last season. He was called up in August and played in 30 games. He hit .191 with the Diamondbacks after hitting .344 with 30 doubles and 32 stolen bases at Triple-A. Elmore played college baseball at Arizona State and was selected in the 34th round of the 2008 amateur draft by the Diamondbacks.