SAN FRANCISCO -- In the third at-bat of his first big league game, Adam Duvall crushed a two-strike slider through the cold night air and into the left field bleachers. Duvall became the 13th Giant to have his first big league hit also be a homer in his debut, and he was surrounded by a crush of reporters and cameras afterward.

"I'm just one man," Matt Cain said in a singsong voice as he walked past. "Just one man!"

That was the problem for the Giants.

Duvall's homer was their lone run in a 3-1 loss to the Cincinnati Reds on Thursday night that was the third in the first four days of this 10-game homestand. The Giants have dropped 12 of 16 overall, and after a win by the Los Angeles Dodgers, their lead in the division is down to just two games for the first time since May 11.

"We're just not swinging the bats very well," manager Bruce Bochy said. "As a group, we're not clicking right now."

The Giants had dropped the first game of a series five consecutive times. Mike Leake had little trouble making it six, striking out a career-high 12 in eight innings. Leake gave up just four hits while improving to 4-0 with a 0.87 ERA in four career starts at AT&T Park.

Through six innings, though, Ryan Vogelsong was just about Leake's equal. A day after Tim Lincecum's no-hitter, Vogelsong gave up five hits and one earned run before a heavy workload ended his night. Vogelsong was predictably hard on himself.

"I rubbed up against him before the game," he said of Lincecum. "It didn't work."

Bochy made a point of shifting the blame elsewhere.

"We got a great start from Vogey," he said. "We've got to get the bats going. We're playing some good teams and facing some great pitching tomorrow (in MLB ERA leader Johnny Cueto), the next series and going forward. It's going to be vital we get going."

After four scoreless innings, the Reds finally did in the fifth. Jay Bruce hit a one-out double, and, after a strikeout of Ryan Ludwick, Vogelsong gave up an RBI double to Zack Cozart.

"I worked my butt off to strike out Ludwick. He's given me trouble in the past," Vogelsong said. "Then you hang a curveball to the eight-hitter and give up a double that scores a run. That chaps my butt a little bit."

The Reds tacked on two runs in the seventh, becoming the second team all season to score off right-hander Jean Machi. Brandon Phillips' solo homer ended Machi's 251/3-inning scoreless streak.

Only strong arms on the infield kept the Reds from adding on. Speedster Billy Hamilton tried to tag up from third on a very shallow pop-up to right in the sixth inning but was thrown out by second baseman Joe Panik. Shortstop Brandon Crawford made a strong throw in the eighth to cut down Phillips at the plate.

The throws wouldn't figure into the result, and neither would Duvall's homer, a shining moment on a night otherwise devoid of them. The 25-year-old was called up Wednesday and was an emergency fill-in for first baseman Michael Morse, who was sick. Duvall struck out in his first career at-bat and popped up in the fifth, but he got all of an 0-2 pitch in the seventh. Still, he thought it might not be enough.

"To be honest, I was just hoping it would go out," he said. "I've heard a lot of talk that it doesn't fly here. It's hard to hit one out."

That's true, especially at night. But Duvall, the Pacific Coast League home run leader (23) at the time of his promotion, might be one of the rare exceptions. His parents watched from seats alongside the home dugout, along with about 10 other friends and members of his family. Duvall wasn't sure if he remembered to look for Mom and Dad after the solo blast.

"It was kind of all a whirlwind," he said. "I'm not sure what I saw. I just made sure to touch all the bases."

  • First baseman Brandon Belt began his rehab assignment with Single-A San Jose. He went 1 for 3 with a single and a hit by pitch (foot) as the designated hitter against Visalia.

    "Overall, I was pretty happy with how it went," Belt said. "Physically, I felt good. I'm seeing the ball a little better than I thought I would so I'll just continue to get better.

  • Second baseman Marco Scutaro (back strain) was a little sore after getting two at-bats in a rookie league game Tuesday, but he was set to play Friday. Bochy said center fielder Angel Pagan would take a couple days off to let his back inflammation subside. Pagan is eligible to come off the disabled list Tuesday.

    The Giants appeared to have dodged a much bigger injury in the late innings. Catcher Buster Posey crouched down in the dirt after taking a foul ball off his left toe, but he stayed in the game.

  • The Giants kicked off their sixth annual Junior Giants Stretch Drive to benefit the Junior Giants baseball program. Donations can be made by visiting JrGiant.org.

    Staff writer Jimmy Durkin contributed to this report.

    FRIDAY'S GAME
    Cincinnati (Johnny Cueto 7-5) at Giants (Madison Bumgarner 9-4), 7:15 p.m. CSNBA

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