SAN FRANCISCO -- For seven innings, it looked like one run of support was going to be enough for Madison Bumgarner, who has been baseball's most dominant pitcher since June 14.
Then the lefty's error keyed a four-run, game-sealing Brewers rally in the top of the eighth inning and Milwaukee escaped AT&T Park with a 6-1 win Wednesday.
The Giants, who were 2-for-22 (.091) with runners in scoring position through the first two games of the series, didn't even advance a runner to second base until the seventh inning.
For the second game in a row, they waited until the seventh to lead an inning off with a baserunner.
The Giants have now lost four of their last five games, 12 of their last 17 and 17 of their last 29. After the Dodgers put up 18 hits and 13 runs against the Cardinals, the last-place Giants trail Los Angeles by 13 games.
Starting pitcher report
Since June 14, Madison Bumgarner had authored a 1.55 ERA, the lowest in the majors. He lowered it further through seven shutout innings Wednesday, until a disastrous eighth inning.
After a double book-ended by two singles tied the game at one, Bumgarner opted to go to third on a sacrifice bunt. Pablo Sandoval was not in position after showing for the bunt, and the ball caromed away to give Milwaukee the lead.
The 24-year-old southpaw did extend his streak of games in which he tossed at least seven innings while allowing three or fewer runs to 10, though. For comparison, Hall of Famer Gaylord Perry was the last Giants pitcher to go 10 straight starts with at least seven innings pitched and three or fewer runs allowed (in 1969).
Bumgarner's final line: 7 IP, 5 H, 4 R, 3 ER, 3 BB, 4 K, 103 P, L.
Santiago Casilla entered for Bumgarner, and he was unable to strand his two inherited runners. Norichika Aoki delivered a single up the middle that plated both Bumgarner's runs and snapped his streak of nine straight games with two or fewer earned runs.
The telecast showed Bumgarner punch the roof of the dugout on Aoki's hit.
Barry Zito made his 2013 relief pitching debut, pitching the ninth inning. He allowed a solo home run to Khris Davis and another run after a walk and two singles.
At the plate
The Giants, who went three-up, three-down in five consecutive innings against the Brewers on Wednesday, are the league's lowest-scoring team since the start of July, a span of 32 games in which the team has scored 94 times (2.94 runs per game).
For the 10th time this season, the Giants provided Bumgarner with one or fewer runs in support.
Poised to go big in the seventh inning with runners on second and third, no outs, and the cleanup hitter stepping to the plate, the Giants went 0-for-2 with runners in scoring position and managed one run on Buster Posey's sacrifice fly. Khris Davis made a spectacular full-extension dive to limit the damage.
When the ball jumped off Posey's bat following one of his patented full-bodied swings in the first inning, the AT&T Park crowd jumped, ready to leave the offensive woes in the past.
But, as things have gone for the Giants lately, the ball held up in left-center field, giving Carlos Gomez enough time to track it into the gap and make the leaping catch.
It was a popular and unfruitful spot for the Giants -- the left-center field gap. Hunter Pence, who had a loud pregame batting practice reminiscent of Andres Galarraga, smashed the first pitch he saw in the third inning. But, again, Gomez was there at the base of the wall in left-center.
Off the bat, both looked and sounded like AT&T Park home runs, a feat the Giants haven't achieved since July 20. They've gone 11 straight home games without leaving the yard, but they're still five games shy of the franchise record, when the team failed to go deep in 16 straight home games last May 15 - June 10.
Brewers starter Marco Estrada, topping out at 90 miles per hour, is not a household name. But he kept the Giants' bats silent like a fire-balling ace. San Francisco managed just one base runner in five innings against Estrada -- a first-inning single up the middle from Brandon Crawford.
Crawford was one of the Giants' few offensive bright spots. After his first-inning single, he also accounted for the team's second base runner, when he drew a 10-pitch walk in the seventh.
Gregor Blanco pinch-hit in the eighth inning and delivered a ground-rule double. It's just his fourth hit in 46 at-bats since the All-Star break (.087).
In the field
The Giants fielded cleanly behind Madison Bumgarner, but it was the pitcher who faltered defensively Wednesday.
After Bumgarner allowed consecutive singles to lead off the second inning, he induced a ground ball to shortstop from Khris Davis and Brandon Crawford teamed up with Joaquin Arias and Brandon Belt to complete the 6-4-3 double play.
Another 6-4-3 double play helped Bumgarner escape the sixth. After a leadoff walk to pinch hitter Caleb Gindl, Bumgarner got Rickie Weeks to bounce to short and Crawford adjusted to a low home to initiate the two-for-one.
Jeff Francoeur, playing center field for the fifth time in his nine-year career, handled the position without incident.
The Giants announced a paid attendance of 41,416, the 222nd regular season sellout at AT&T Park. You can't keep 'em away.
The Giants and Brewers wrap their four-game set Thursday afternoon as Tim Lincecum (5-11, 4.43 ERA) takes on right-handed pitcher Donovan Hand (0-3, 3.60 ERA), who will be making his seventh major league start. No one on the Giants roster has faced him in the bigs.