SAN FRANCISCO -- The San Francisco Giants realize sweeping a three-game home series from the Philadelphia Phillies does not make them title contenders again.

But it does get them three games closer to that ultimate goal.

Catcher Andrew Susac belted a three-run home run in a four-run fourth inning, and rookie Chris Heston won his ninth game as the Giants won a third straight from the Phillies, 4-2 Sunday afternoon.

"That's what we wanted to do: finish up (the first half) on a positive note," said Giants manager Bruce Bochy, whose team (46-43) settled into second place in the National League West at the All-Star break, trailing the Los Angeles Dodgers by 4 1/2 games.

"You hate to have a four-day break after how we played this series," Bochy continued. "But I'll take it."

The Phillies lost their fifth in a row and completed a 2-8 trip. Their 29-62 record is the worst in the majors, and the 62 losses are a pre-All-Star-break franchise record.

"I like what I see," Phillies interim manager Pete Mackanin said of Sunday's starter, Chad Billingsley, in stressing a positive in his postgame interview. "He's showing a lot of promise."

Center fielder Angel Pagan and catcher Buster Posey had three singles apiece for the Giants, who followed up 22- and 15-hit explosions against Philadelphia pitching with an 11 -hit attack in the series finale.

The sweep was the Giants' first over the Phillies since the first year of AT&T Park in 2000.

"Very positive for us. We knew we had to do it," Susac said of the sweep. "Guys are confident. We're swinging it well."

Heston (9-5) added to his NL lead among rookies not only in wins but also in strikeouts (89) and innings pitched (111 2/3) when he fanned seven in 6 2/3 innings.

He gave up three consecutive hits, including an RBI single to Phillies first baseman Ryan Howard, in the seventh inning before leaving in favor of left-hander Josh Osich. Heston allowed seven hits and just the one run. He did not walk a batter.

"He's been a savior," Bochy said of his rookie. "You lose (Matt) Cain. You lose (Jake) Peavy. You need somebody from your organization to step up and help you out.

"In order to get to where you want to go, you have to have a surprise or two. He's been our steady guy in the rotation. I'm proud of this guy."

Howard also drove in the Phillies' second run with a two-out single in the ninth against Giants closer Santiago Casilla, who nonetheless registered his 23rd save.

Neither team scored before the Giants finally got to Billingsley (1-3) in the decisive fourth inning.

After Posey and right fielder Hunter Pence singled, the Giants got a two-out, run-scoring hit by shortstop Brandon Crawford.

Susac followed with a blast to center field, his third homer of the year, to give Heston a four-run cushion.

"Anytime they're going out there putting up runs, that takes pressure off you," Heston admitted. "If you can put up zeroes after your team has scored a couple, that's big for your team."

The home run was the Giants' only extra-base hit of the game.

Osich pitched 1 1/3 innings of shutout relief before handing the ball to Casilla with a three-run lead in the ninth.

Pence had two hits for the Giants, who batted .419 (18-for-43) with runners in scoring position in the series.

Howard, left fielder Cody Asche and center fielder Ben Revere each collected two of the Phillies' nine hits. Revere finished the first half with at least one hit in 10 of his last 11 games, raising his average to .297.

Billingsley allowed four runs and 10 hits in five-plus innings. He didn't walk a batter while striking out two.

"A lot of singles and that one big hit," Billingsley noted. "It happens."

NOTES: Giants C Buster Posey is 15-for-29 (.517) in his career against Phillies RHP Chad Billingsley. ... Giants manager Bruce Bochy announced that RHP Tim Hudson (sore right shoulder) would return to the rotation immediately following the All-Star break. RHP Tim Lincecum (bruised right forearm) will not. Bochy would not reveal which of the current members of the rotation would be demoted (probably to the bullpen). ...The Giants open the "second half" Friday at Arizona. ... The 1997 Phillies were 24-61 before the All-Star break, the franchise's highest "first-half" loss total before this year. ... The Phillies have lost 17 of their last 19 road series. ... Phillies manager Pete Mackanin decided upon his starting pitchers for the three-game home series against the Miami Marlins that immediately follows the All-Star break. LHP Adam Morgan will start Friday, Billingsley on Saturday and LHP Cole Hamels on July 19.