The Athletics originally drafted Parker in the fifth round of the 2009 draft. The 25-year-old spent the 2012 season at Triple-A, where he posted a .256/.327/.390 batting line in 375 plate appearances. Parker, a left-handed hitter, has spent most of his minor league career playing first and third base.
Byrd, 26, signed with the Brewers as a minor league free agent in 2010. He spent three years in the Milwaukee farm system, pitching at Double-A Huntsville in 2012. He posted a 2.59 ERA with 8.8 K/9 and 4.4 BB/9 in 73 innings of relief work last year.