SAN DIEGO Petco Park is at sea level, so the Giants should not be out of breath after running the bases a bit.But youre never conditioned for 18 runs in two games here. Thats where the tally stands after five different players collected multiple hits and Joaquin Arias led the rallying charge in an 8-7 victory over the San Diego Padres Saturday night.Pablo Sandoval needed oxygen after hitting a triple, racing home on a sacrifice fly and chugging home from second base on a single. His strained hamstring appeared to handle the pace, which continued to be frenetic in a venue better known for eked-out victories and low-scoring losses.Giants manager Bruce Bochy played this one just about perfectly. He aggressively got Barry Zito out of there after four innings and the club trailing 4-1, then watched as pinch hitter Ryan Theriot singled to start a four-run rally.Bochy sat Brandon Crawford even though the shortstop was batting .419 over a career-best nine-game hitting streak, deciding to go with Arias instead because Padres left-hander Eric Stults was holding lefty hitters to a .142 average.Arias responded with a solo home run and a pair of RBI singles.And finally, Bochy lifted Jeremy Affeldt in the ninth after the Padres scored twice and put the tying run on base. Clay Hensley made that move pay off too, striking out Mark Kotsay to end it.The Giants kept the line moving, as Bochy often says. They didnt strike out until Angel Pagan went down looking to end the sixth. They put the ball in play, and good things happened including sacrifice flies by Marco Scutaro, Hunter Pence and Buster Posey, who hit rockets to right field all night.The Giants have seen more sacrifices than the graven images chapter in Exodus. They lead the major leagues with 46 sacrifice flies.Starting pitching reportBarry Zito threw just 33 strikes among his 60 pitches. His command most gloriously escaped him on one specific offering to Carlos Quentin in the second inning.Zito lost the pitch out of his hand and it popped straight in the air, landing like a lawn dart 20 feet in front of the plate and then rolling toward the batter. Call it a mega-eephus. Zito didn't appear amused as he called for another baseball.That wasnt the pitch that cost Zito, though. He most wanted back the 1-0 cutter down the middle that Chase Headley turned around for a three-run home run in the third inning. It was Headleys eighth homer in August, which leads the majors. He also leads the majors with 24 RBIs this month.Zito retired five of his next six batters to get through four innings, but manager Bruce Bochy had seen enough. With the Giants trailing 4-1, he had Ryan Theriot pinch-hit for Zito leading off the fifth.It marked the fourth time in his last five outings that Zito failed to complete six innings.Bullpen reportEric Hacker had a golden chance for his first major league victory. He entered a 5-4 game after the Giants had rallied to take the lead, and the official scorer couldnt award the victory to Zito because he didnt pitch the five required innings to qualify for the decision.Hacker tossed a scoreless fifth, but the 29-year-old Texan lost his claim when he served up a tying home run to Carlos Quentin leading off the sixth.Then the bullpen stabilized for a spell. Jose Mijares got an out to end the sixth and another to start the seventh while picking up his first victory as a Giant. Santiago Casilla retired both batters he faced and Sergio Romo worked a scoreless eighth.Jeremy Affeldt got two quick outs in the ninth, but a walk and two singles got the Padres within a run. Hensley entered to face pinch hitter Mark Kotsay, getting ahead with sinkers before getting him to swing through a change-up to end it.Hensley recorded his third save of the season.At the plateArias rewarded Bochy for putting him in the lineup. He connected for the second home run of his career (in 235 at-bats), a solo shot in the second inning, and kept on hitting the ball hard with runners on base.It was Theriot who sparked the Giants to their four-run rally in the fifth. He singled, Angel Pagan stayed on an outside pitch while hitting a sharp double to left field and Marco Scutaro continued yet another productive night with a 400-foot sacrifice fly that center fielder Cameron Maybin caught on the run near the wall.The Giants received a break after that after Headley made a mental mistake. The third baseman lunged to catch Pablo Sandovals hard grounder and inexplicably threw home when he had no shot at getting Pagan. It was scored an RBI and a fielders choice, although it more closely resembled fielders temporary insanity.The Giants took advantage, as Sandoval chugged around to third base on Buster Poseys double and scored the tying run on Hunter Pences sacrifice fly. Arias followed with a sharp single that scored Posey from second base to give the Giants a 5-4 lead.Scutaro set the table again when he and Sandoval singled off Brad Brach to put runners at the corners with no outs. Posey, who stung the ball to right field all game long, hit a tie-breaking sacrifice fly and Arias came through with his third RBI hit of the game.In fieldSandoval made the spectacular stop of the game, lunging to his right and making a clean stab of Headleys hard grounder in the fifth. Sandoval gathered himself without delay and made a strong throw to end the inning.But the most valuable defensive play might have come in the second inning, when the Padres netted just one run despiteloading the bases with no outs. Cameron Maybin hit into a fielders choice that might have been a double play if Arias had been a little swifter to cover second base. But inexplicably, Maybin tried to steal with one out and a runner at third. Catcher Buster Posey made a perfect throw to gun down Maybin and minimize what couldve been a big inning.And hey, that 3-6-3 double play was pretty darn nice behind Sergio Romo to end the eighth. An extra pudding cup for Brandon Belt, if he wants it.AttendanceThe Padres announced 33,849 paid. Randomly, the Teenage Mutant Ninja Turtles made an appearance. Youre welcome, Brian Wilson.Up nextThe Giants go for a three-game sweep at Petco Park with a Sunday afternoon game behind Ryan Vogelsong (10-6, 2.72), who is coming off his worst outing as a Giant. Hell try to get back in a groove against left-hander Clayton Richard (9-12, 3.91).