"David didn't have his greatest stuff but he was still really good. His fastball was a really good pitch today," Rays manager Joe Maddon said. "We just have to score a couple points and he gets the win."
The Rays lost for just the second time in their past 13 games. A victory Wednesday would have lifted Tampa Bay (53-55) to .500 for the first time since late April.
Maddon said he also expects Price to remain with the Rays past the deadline.
"Obviously, if you were to lose some really important players and some friends, that would be difficult," Maddon said, "but we are in a business. We've done it before and we've survived. I'd much prefer that he was here."
Maldonado put the Brewers up 2-0 with a two-run single in the second, an inning that included two walks. It was just the second time this season Price walked a pair in the same inning.
After Aramis Ramirez had a third-inning run-scoring single, Maldonado made it 4-0 when he drove in a run with a double in the sixth.
Maldonado got his third hit on an RBI single in the eighth.
Gallardo won for the first time since beating Arizona on June 19 to stop a six-start winless streak.
Jeremy Jeffress gave up two of his three hits in the ninth before Zach Duke walked Logan Forsythe to load the bases with two out. Brewers closer Francisco Rodriguez entered and got his 31st save by striking out Yunel Escobar.
Price had gone eight or more innings in eight of his previous nine starts. He missed a chance to become the first Rays pitcher to win six games in a month.