After the 2007 season, the Twins traded Garza along with Jason Bartlett and Eduardo Morlan to the Tampa Bay Rays for Delmon Young, Jason Pridie, and Brendan Harris. Garza had a successful season with the Rays, going 11–9 while posting a 3.70 ERA. He also earned MVP honors for the ALCS in which he helped the Rays beat the Boston Red Sox by posting a 1.38 ERA in two starts, and earning the decisive victory in game 7 of the ALCS.