San Francisco Giants’ starting pitcher Ryan Vogelsong (32) walks off the field after the second inning of their game against the Arizona Diamondbacks
San Francisco Giants' starting pitcher Ryan Vogelsong (32) walks off the field after the second inning of their game against the Arizona Diamondbacks at AT&T Park in San Francisco, Calif. on Thursday, April 9, 2014. (Nhat V. Meyer/Bay Area News Group)

SAN FRANCISCO -- The Giants' struggles at the back of their rotation continued Thursday night, even if the outcome of their game with Arizona wasn't resolved until a couple of hours after starter Ryan Vogelsong had departed.

Vogelsong labored through five innings, giving up seven hits and four runs against the Diamondbacks at AT&T Park. The Giants staged a valiant rally to give him a lead they carried into the eighth inning, but they couldn't hold it and ultimately lost 6-5 in 10 innings.

Tony Campana's two-out, full-count single over second base in the top of the 10th against the Giants' eighth pitcher, Yusmeiro Petit, scored Cliff Pennington with the game-winner in the 4-hour, 10-minute game. Pennington had singled with one out against Petit (0-1) and stolen second base.

It looked like the Giants were headed for a loss much earlier. Vogelsong trailed 4-1 after the first three innings, but was ultimately taken off the hook by Michael Morse, who doubled home two runs in the bottom of the fifth to give the Giants their first and only lead of the night, 5-4.

"We've been swinging the bats great, you can't say enough about that," said Vogelsong. "(The offense) gave us a chance. I don't feel like I gave us much of a chance."

Indeed, after Morse's big hit, Vogelsong came out to start the sixth inning but promptly surrendered a double to Mark Trumbo, and manager Bruce Bochy was forced to go to the bullpen.

"I've got to be able to get through that sixth inning and take some of the stress off the bullpen," Vogelsong said. "A lot of this comes back to me tonight."

Third baseman Pablo Sandoval could take a bit of the burden, too. Sandoval's two-out throwing error over the head of first baseman Brandon Belt allowed the Diamondbacks to score the tying run in the bottom of the eighth. Sandoval tried to rush a throw on a Campana chopper and Bochy said his third baseman probably shouldn't have even attempted to throw out the speedy Arizona leadoff hitter.

"You have to keep your poise, and he just got in a rush mode there, that's all," the manager said. "With the game on the line, you have to be a bit more cautious and understand the situation. If you don't get him, you don't get him, but just try to make a good throw. It got away from him.

Sandoval also went 0 for 3 to see his average drop to .132, lowest among the Giants' everyday starters. He hit into a double play with two on and nobody out in the third, and it required a surprise bunt by Buster Posey to squeeze a run out in that inning. Sandoval also flew out to right with the bases loaded in the eighth.

Arizona Diamondbacks’ Paul Goldschmidt (44) hits San Francisco Giants’ Buster Posey (28) in the back of the head at first base after Posey
Arizona Diamondbacks' Paul Goldschmidt (44) hits San Francisco Giants' Buster Posey (28) in the back of the head at first base after Posey bunted in the third inning at AT&T Park in San Francisco, Calif. on Thursday, April 9, 2014. San Francisco Giants' Angel Pagan (16) would score on this play. (Nhat V. Meyer/Bay Area News Group) (Nhat V. Meyer)

As for Vogelsong, he wound up walking one, hitting two batters and striking out five in his five-inning stint. He pitched a scoreless first inning, but immediately ran into trouble in the second. With one out, he grazed Miguel Montero with a pitch, walked Trumbo and surrendered an opposite field single to Gerardo Parra to load the bases. Pennington then lined the first pitch he saw to center for a two-run single.

Arizona added two more in the third on a two-run double and it looked like Vogelsong was on the ropes, but he actually rallied with scoreless innings in the fourth and fifth. After the game, however, he wasn't prepared to accept his comeback as a consolation prize.

"It was better, but it's still not where I want to be," he said. "I probably just need to be more aggressive."

Bochy was kinder in his assessment of Vogelsong.

"He could have caved in, giving up four there," Bochy said. "But he did rally and got us to the sixth inning. Hopefully, he's encouraged the way he bounced back."

The manager reserved most of the praise for the bullpen, which gave the offense plenty of opportunities to put the game out of reach in the late innings.

"That's a frustrating loss," he said. "We had bases loaded one out (in the eighth) and couldn't get a run in, and then they get a big two-out hit (in the 10th), and that's what wins games for you. We're supposed to win these types of games at home."

Petit (0-1) wound up taking a tough loss after giving the Giants two scoreless innings on Wednesday. Campana's winning hit was a jam shot that just eluded the glove of second baseman Brandon Hicks.

-- Closer Sergio Romo appeared to be in distress on the bench after pitching a scoreless ninth inning, but Bochy said Romo was merely suffering from stomach cramps after a bout with the flu.

-- Angel Pagan's third-inning single gave him a 10-game hitting streak to open the season.

Follow Carl Steward on Twitter at twitter.com/stewardsfolly.

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