SAN FRANCISCO -- Christian Arroyo continued to inject life into the Giants, shattering an eighth-inning tie Friday night with a leadoff home run as San Francisco topped the San Diego Padres, 4-3.
Arroyo hit his second homer since the Giants summoned him from Triple-A Sacramento, pulling an 0-1 fastball from San Diego reliever Ryan Buchter over the left-field barrier. Mark Melancon pitched the ninth to convert his fifth consecutive save opportunity.

Arroyo left a definite impression in his first handful of Major League games this week. He stroked his first Major League hit Tuesday off Dodgers ace Clayton Kershaw, hit a two-run homer Wednesday that ignited a victorious Giants comeback from a 3-0 deficit, and now this.
"Obviously at that point in the game it was huge, but for me, I was not trying to hit a home run," Arroyo said. "I was just trying to get the [bat] head out, see a pitch over the plate, try to get on base. But I got a good pitch, backspun it, elevated it a little bit, [and I] was fortunate enough [for it] to go out."
Neither starter was involved in the decision but both were effective. San Francisco's Jeff Samardzija allowed three runs (two earned) in seven innings and saved his best for last, escaping a second-and-third, one-out jam in the seventh.

Giants manager Bruce Bochy said he kept the bullpen quiet and left Samardzija in the game to demonstrate confidence in the right-hander.
"He's real smart at picking his spots at when to show confidence in guys," Samardzija said. "I made some good pitches and got out of it."
San Diego's Luis Perdomo surrendered three runs (one earned) and six hits in six innings. He exited after throwing just 69 pitches. After the game, manager Andy Green noted Perdomo's struggles against the top of the Giants' order as the reason he wouldn't let him begin a fourth trek through the lineup.
"I didn't think I was going back out at that point," said Perdomo, who was making his second start since coming off the disabled list with shoulder inflammation. "I know that we have a really strong bullpen and a seventh-inning guy. So I was going to rely on them."

MOMENTS THAT MATTERED
Seizing opportunity: Scoring runs has been a problem for the Giants, particularly early in games. Entering Friday, they had scored four first-inning runs all season. So it was significant when they scored in the first on shortstop Erick Aybar's two-out error, which resulted in a second unearned run coming across on Conor Gillaspie's single. The two-hopper that Aybar muffed ultimately reinforced the notion that good things happen when the ball's put in play. The last time the Giants scored in the first inning occurred April 16 against Colorado, when they tallied three runs.

"That's a play he expects himself to make, I can guarantee you that," said Green. "And that's a play he makes 99 percent of the time. The reality is, over the course of a season, everybody misses a ground ball, and that one stung us."
Soaring Schimpf: Samardzija cruised through four before plunking Yangervis Solarte to start the fifth. Ryan Schimpf made the Giants right-hander pay, as he launched his third homer in as many nights. The blast, which represented the Padres' first hit of the game, tied the score at 2 and marked Schimpf's ninth hit of the season -- six of which have left the yard.
"We've always known he drives the ball out of the ballpark," Green said of Schimpf, who has emphatically broken out of his 1-for-28 slump. "... It's good to see him start to get that back."

QUOTABLE
"[Arroyo's] got pop. He's not a guy who's trying to hit home runs. He's just trying to put a good swing on it. He drives the ball, as you saw tonight and since he's been up here. … He's going to get more power as he gets a little older. Here's a young kid just getting settled in. We're not asking him to hit home runs, trust me. But it's good to see the way he's letting it go." -- Bochy, who also observed during Spring Training that the 36 doubles Arroyo hit last season at Double-A Richmond provided a sign of budding power
SOUND SMART WITH YOUR FRIENDS
Arroyo became the first Giants rookie to hit a go-ahead home run in the eighth inning or later since Mac Williamson did so on June 8 against Boston left-hander David Price.
UPON FURTHER REVIEW
The Giants challenged a second-inning call, believing Hunter Pence had been grazed by a Perdomo pitch -- contrary to an umpire's ruling. A review overturned the call and awarded Pence his base.

WHAT'S NEXT
Padres:Jhoulys Chacin fouled a ball off his foot Monday, but X-rays came back negative, and the veteran right-hander will make his scheduled start Saturday in San Francisco. First pitch is slated for 6:05 p.m. PT. Chacin has been dreadful on the road this season (11.93 ERA), but very sharp at AT&T Park throughout his career (1.41 ERA).
Giants:Player Page for Matt Cain (2-0) will attempt to remain undefeated Saturday as San Francisco and San Diego collide in a 6:05 p.m. PT encounter. Cain has improved lately, relying heavily on a two-seam fastball to record a 1.00 ERA in his last three starts.
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