And while he delivered a jewel, Milwaukee's offense was confounded and mastered by two-time Cy Young Award winner Johan Santana and the new 1-2 punch at the door-slamming end of the Mets' bullpen in a 1-0 loss before a crowd of 36,312 at Citi Field.
The Brewers collected five singles and no walks against Santana, got no hits off eighth-inning setup man J.J. Putz and singled once against closer Francisco Rodriguez.
In fact, the Brewers didn't advance a runner beyond first base, as they watched their record fall to 3-8.
"Keep banging man, keep grinding man," Brewers center fielder Mike Cameron said quietly afterward in the sparsely populated visiting clubhouse. "Don't hang your head on a couple of losses. They were tough losses, as all of them are. But I guess the good thing is we've been in games and have given ourselves a chance to win.
"Now we just have to find a way to get over the hump."
The loss left Milwaukee 1-4 in one-run games, including 0-2 here on Friday and Saturday.
"This happens, whether it's now or later in the season," said second baseman Rickie Weeks, who made a costly error on a play at first base when the game was decided in the bottom of the seventh inning. "Most teams go through this. I think a win is going to spur us."
Gallardo, the Brewers right-hander with a 1-1 record, a 6.94 ERA heading into Saturday and a world of potential, stepped up to the task of trying to keep Mets batters off the bases while his teammates tried to muster some offense against Santana.
Gallardo worked six strong innings, yielding just five hits, striking out seven and walking two, before he gave way to right-hander Carlos Villanueva in the seventh.
"The old bugaboo -- walks," Milwaukee manager Ken Macha said. "[We] walked the No. 8 hitter to lead off the seventh inning and mishandled the ball, and that's pretty much all there was to it. Then they brought in the guys they brought here to handle the eighth and ninth inning and that's pretty much what they did."
Villanueva walked catcher and No. 8 hitter Ramon Castro to start the bottom of the seventh. Alex Cora, batting for Santana, dropped a bunt down the first base side that was handled cleanly by Prince Fielder. But Weeks, who'd moved over to cover first base, mishandled the throw. The Mets wound up with runners on the corners and no outs.
"I just missed it," said Weeks, offering no excuses.
Jose Reyes then hit a ball that deflected off the thumb of Villanueva's glove hand and caromed toward shortstop. Pinch-runner Omir Santos scored from third on the fielder's choice that produced the only run of the game.
"I thought I threw the ball well except for that walk," Villanueva said. "In a tight game like that, a minimal thing can cost you the game, I guess."
Macha didn't phrase it quite so calmly.
"We've had plenty of walks," the manager said. "We've had enough walks. It's the No. 8 hitter and it's late in the ballgame. Killer, leadoff walks late in the game."
The Mets had only one good scoring opportunity, in the first, through the first five innings. Gallardo had a good fastball early, and finally got a feel for his breaking ball.
"He's a great pitcher," Gallardo said of Santana. "It was going to be kind of tough, but I was going to go out there and try to do the same thing. I knew if I threw well, it was going to be close in the ninth inning."
It was, but the struggling Brewers weren't having much luck against Santana, who struck out seven and didn't walk a batter while improving to 7-0 with a 1.33 ERA in is last seven starts at home. He's 2-1 with a 0.46 ERA in three starts this season. The Brewers had singles in the first, second, third and fifth innings, but no leadoff batter on base until Corey Hart led off the sixth with a single to left.
"He had great command of all his pitches," said Brewers right fielder Ryan Braun, who singled off Santana and Rodriguez. "The ball just explodes out of his hand. Everything looks the same. He commanded both sides of the plate. He rarely missed his spots at all to anybody."
Milwaukee had no success in the one inning it faced Putz, the former Mariner, and had one hit against Rodriguez, the former Angels' closer.
The game ended when Braun, who led off the ninth with a single, was thrown out on an attempt to steal second just as J.J. Hardy was going down on strikes.
"Kind of the epitome of our luck right now," Braun said.
Kit Stier is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.