SAN FRANCISCO -- Buster Posey rocketed his first home run of the season and Barry Zito pitched brilliantly for the third time in four starts, leading the San Francisco Giants to a 5-0 victory on Sunday and a three-game sweep of the San Diego Padres at AT&T Park.
In helping the Giants quickly erase the sting of having been swept at Milwaukee earlier in the week with a sweep of their own, Posey connected off losing pitcher Eric Stults (2-2) with Pablo Sandoval aboard and two outs in the fifth inning, adding two runs to what already was a 3-0 lead.
The home run was Posey's first since Oct. 2 when he took the Los Angeles Dodgers' Chris Capuano deep.
The two extra runs were hardly needed with Zito (3-1) having reverted to the form that saw him begin the season with 14 consecutive scoreless innings against St. Louis and Colorado. He gave up five hits in his third seven-inning masterpiece of the season before turning the game over to Chad Gaudin, who completed the Giants' second combined shutout of the series with two innings of one-hit relief
Coming off a nine-run disaster at Milwaukee on Tuesday, Zito stranded runners in scoring position in each of the first two innings and used all of AT&T spaceous outfield, getting nine of his 21 outs on fly balls. He struck out four and walked one.
Nick Hundley had two of the Padres' hits off Zito, both singles.
Sandoval had two of the Giants' eight hits off two Padres pitchers, including a run-scoring single that capped a three-run third. Angel Pagan provided the big blow of that inning, a two-RBI double that opened the scoring and set the stage for Sandoval's run-producing hit.
Andres Torres, getting the start in left field in place of Gregor Blanco, also had two hits for the Giants, including a double that opened the three-run third.
Posey's home run was a no-doubter and came one pitch after Padres shortstop Everth Cabrera couldn't handle Sandoval's hard grounder in the hole for what could have been the third out of the inning against the plodding slugger.
The homer, which landed 10 rows deep in the left-field bleachers, made it 5-0 and came in Posey's 64th plate appearance of the season. He began the day having had just five extra-base hits and six RBI while playing in 16 of the Giants' first 18 games.
Posey caught all three games of the series, including back-to-back starts by two pitchers -- Tim Lincecum and Zito -- who often work with Hector Sanchez.
Two hitters who have done much of the Giants' offensive damage this season during Posey's cool start pooled their talents again in a three-run third that broke a scoreless tie.
With runners on second and third and one out, Stults went 3-and-0 on the clutch-hitting Pagan with a base open and struggling Marco Scutaro on deck. But the left-hander made the mistake of trying to sneak a strike by Pagan and paid the price when the switch-hitter smacked a two-run double to center field, his seventh go-ahead RBI of the young season.
Torres, who had opened the inning with a double, and Brandon Crawford, who had singled, scored the runs against Stults, who retired the Giants in order in the first two innings.
After Scutaro flied to right for the second out, Stults went 0-and-2 on Sandoval and tried to bounce an off-speed pitch on home plate. But the aggressive swinger went down and got it, grounding a single to center to score Pagan and make it 3-0.
The RBI was Sandoval's 17th of the season and bloated his batting average with runners in scoring position to .550 (11 for 20). Fourteen of Sandoval's 17 RBI have come in those situations.
NOTES: Padres left fielder Kyle Blanks had to be removed from the game in the bottom of the sixth after crashing into the padded left-field wall sunglasses-first, one step after catching Joaquin Arias' bid for extra bases. Blanks was able to walk off the field without assistance. ... Giants starting pitchers had allowed 31 earned runs in 40 1/3 innings over seven games before seeing the Padres and giving up just two runs in 12 2/3 innings in 3-2 and 2-0 wins on Friday and Saturday nights. ... Giants manager Bruce Bochy drew a quick conclusion from his experiment of moving the hot-hitting Crawford up in the lineup: He's a better hitter in the eight-hole. Crawford went 0 for 6 in the first two games of the series when bumped up two slots to No. 6, then singled in his first at-bat Sunday when rerouted to his familiar eighth spot. ... The Padres and Giants will square off again next weekend in San Diego, with Sunday's starters -- Stults and Zito -- tentatively scheduled to face off again Saturday in the middle game of the three-game series. ... One of the biggest outs Zito recorded early in the game, coincidentally, came with Stults at the plate. With two on and two outs in the second, Stults, who belted a three-run homer in his previous start, made solid contact and flied to medium-deep right field. Stults smacked 23 home runs as a center fielder at Bethel College in Indiana. Stults singled to right in his second at-bat against Zito.