The Detroit Tigers will trade Dontrelle Willis to the Diamondbacks pending completion of a physical, a major league source told FanHouse. Willis was dealt for RHP Billy Buckner. The Tigers designated Willis for assignment on Saturday, giving them 10 days to trade him or pass him through waivers. Willis went 1-2 with a 4.98 ERA in nine appearances for the Tigers this season, walking 29 and striking out 33.