Garza returns from the 15-day disabled list after experiencing radial nerve irritation in his right arm during his second start of the season.
Ruggiano was hitting .300 with one RBI in five games for the Rays this season. The 26-year-old outfielder was named Durham's Player of the Year in 2007 after leading the Bulls with a .309 average, 20 home runs and 73 RBIs.
"Primarily to get him more at bats," Rays manager Joe Maddon said, explaining the move. "It's not really good to have him sit on the bench here. We haven't had much of an opportunity to use him. We're kind of covered in the outfield right now. So we primarily wanted him to get more at-bats. And we sent him back to do that."
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.