The ring, which has an estimated worth of $30,000, was taken during a burglary of Garza's Fresno County home between Jan. 26 and Tuesday, according to the Fresno Bee.
Awarded the ring as a result of beating the Boston Red Sox in the 2008 AL Championship Series as a member of the Tampa Bay Rays, Garza was the Most Valuable Player in the series.
Along with multiple white diamonds and one yellow diamond, Garza's name is engraved on the inside of it.
Quinn Roberts is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.