Mills, a fourth-round selection in the 2007 First-Year Player Draft, made his big league debut for the Blue Jays in 2009, but he has moved around a bit in recent seasons. He was traded to the Angels in 2011 and claimed off waivers by the Rangers last season. Texas released Mills on July 18 of last season.
Mills has a career record of 4-4 with a 6.98 ERA in the Major Leagues. He signed with Milwaukee before this season and pitched to a 4-2 record and a 1.56 ERA for Triple-A Nashville. Mills was then acquired by Oakland for cash considerations in June, and he went 1-1 with a 4.41 ERA for the A's.
Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.