The A's led the AL in ERA through Sunday but had dropped to last in the AL West, seven games behind the Rangers, thanks to a 5--13 stretch in which they scored just a tick over three runs per game. Blame the player development team. Homegrown A's—players who made their big league debuts with Oakland—have combined for 40% of the team's plate appearances and a brutal .232/.301/.314 line. The failure of that core, which includes Kurt Suzuki and Landon Powell, Daric Barton, Mark Ellis and Cliff Pennington, is the biggest reason that the A's are again falling short of expectations. It's time for Oakland to exchange defense for offense—by trade or by promoting prospects Jemile Weeks and Michael Taylor—before they waste yet another year of great pitching.