The Athletics and Brewers made a minor-league trade Wednesday, with Oakland acquiring reliever Darren Byrd from Milwaukee in exchange for third baseman Stephen Parker, the clubs announced. Byrd, 26, spent 2012 at Double-A Huntsville, where he recorded a 2.59 ERA with 71 strikeouts against 36 walks in 73 innings. Control has been an issue for Byrd since promotion to Double-A in 2011. He has walked 4.5 batters per nine innings in 137 frames at the level. Parker, 25, spent 2012 at Triple-A Sacramento and posted a .256/.327/.390 batting line with seven home runs and five triples in 375 plate appearances. Parker struggled to make contact in his first full season at the highest minor league level. He struck out in a career-high 24.8 percent of plate appearances.