Miller appeared in 33 games for the Athletics and pitched 48.2 innings with a 2.59 ERA, 44 strikeouts and a .217 opponents batting average. He was originally drafted in the 8th round by the Colorado Rockies in 2004.
The A's signed Miller to a minor league contract at the start of the 2012 season and he made his way to the majors by April 25. He had success with the A's but struggled with his pitch control at times, issuing 27 walks over the course of his 48.2 innings.
Miller is mostly a two-pitch pitcher, relying on a mid-90s fastball and a low-80s slider. After being with the Rockies organization in 2006, Miller spent a majority of his career with the Baltimore Orioles, where he made his professional debut in 2008. He resigned with the Rockies in 2011 on a minor league contract.