The Tigers claimed Diaz off waivers from the Diamondbacks on Friday, Nick Piecoro of The Arizona Republic reports.
Diaz was designated for assignment last weekend after he was tagged for seven runs on seven hits and one walk across two-thirds of an inning in last Saturday's loss to the Twins. The 25-year-old still sports a high-90s fastball and potentially plus slider despite major control and command issues, and he'll get a fresh start in Detroit's organization.