Despite surrendering a solo home run to Brandon Inge in the second, Garza looked well in command entering the fourth inning. But after retiring Miguel Cabrera on a groundout to start the inning, bad things began to happen when Garza walked Aubrey Huff and Carlos Guillen, which teed it up for the Tigers' bats.
"I thought Garza walking Huffy and Guillen were probably the two biggest plays of the night because [Garza] had good stuff, he had really good stuff," Rays manager Joe Maddon said.
Inge followed the walks with a single to load the bases before Gerald Laird, Adam Everett and Curtis Granderson strung together consecutive doubles to score five runs and push the lead to 6-0.
"Two walks got me. I walk Huff and Guillen, two runners on with one out, and it's real easy to score there," Garza said. "That's all it is. I walked those two guys, and that's what started the rally."
Tigers manager Jim Leyland thought the home run to Inge made an impact on Garza.
"I actually think the ball he hung to Inge shook him up a little bit," Leyland said. Garza is "one of the best. He's got great stuff. He can be overpowering. He's got a good assortment of pitches. He's a very aggressive young kid, and we were fortunate we got to him tonight."
Garza lasted five innings, taking his ninth loss of the season against seven wins. The six earned runs were the most he's allowed since giving up a season-high seven earned runs on April 19 against the White Sox.
Meanwhile, Tigers starter Rick Porcello kept the Rays silent for most of his 5 2/3 innings of work, which saw him allow just one run on four hits.
"We threw a lot more fastballs today actually than we had in the past," Porcello said. "We were getting ground balls, and even the ones where they got on base, they were taking bad swings. We didn't want to change anything up there. Over the past couple starts, I've tried to throw more four-seamers."
Rain delayed the start of Friday night's game by 16 minutes. Maddon said the soggy field didn't help the Rays against Porcello.
"He really had a lot of movement on his fastball," Maddon said. "When you see guys just chopping balls into the front of the home plate area, which was really manicured nicely soft -- the ball was just exploding into that mud there -- you can see that the guy has some really good late movement."