Updated

Chad Gaudin struck out eight over seven stellar innings of three-hit ball, as the San Francisco Giants blanked the Arizona Diamondbacks, 2-0, Friday in the opener of a three-game series at AT&T Park.

Buster Posey and Hunter Pence each knocked in a run in the first to provide more than enough run support for Gaudin (4-1), who scattered three singles over his outing to improve to 4-0 over seven starts since moving into the Giants' starting rotation on June 2.

Four relievers combined to keep the D'backs off the board in the eighth before Sergio Romo retired the visitors in order in the ninth to secure his 22nd save of the season and send the Giants to their fourth victory in five games.

"To come out after the break and win the first game and start the second season off on a good note is exactly what everybody in this clubhouse wanted to do," Gaudin said. "Everybody put together and just worked and battled and we came out on top."

Arizona starter Ian Kennedy (3-7) was tagged with his third straight loss after giving up two runs on five hits and three walks over six frames. Kennedy, who hasn't won since June 1, started and absorbed the loss in Arizona's last game prior to the All-Star break.

Miguel Montero and Adam Eaton each collected two of Arizona's five hits as the Diamondbacks dropped their second straight game and saw their lead atop the NL West slip to just 1 1/2 games over the Dodgers, who downed the Nationals earlier Friday.

"We had no offense going on at all tonight," Arizona manager Kirk Gibson admitted. "They just shut us down."

San Francisco did all its damage in the first, as Gregor Blanco worked a leadoff walk and scored two batters later when Posey laced a double to center.

Posey moved to third on Pablo Sandoval's groundout before scoring on Pence's single to left to push the margin to 2-0.

Arizona, meanwhile, struggled to put anything together until the eighth, when Gaudin was lifted in favor of Javier Lopez.

After Lopez flied out Gerardo Parra, Sandy Rosario took over on the mound and served up a single to pinch-hitter A.J. Pollock.

Jose Mijares entered from the bullpen and lined out pinch-hitter Cody Ross, but Eaton kept the frame alive with a bunt single.

Santiago Casilla then came on to face Aaron Hill, who walked to load the bases for Paul Goldschmidt. However, Mijares got Goldschmidt to ground into a force out to end the threat.

Game Notes

Arizona has lost six consecutive second-half openers ... Kennedy is 0-4 in his last eight starts ... Romo has a 29-game scoreless streak against the D'backs, tossing 21 2/3 consecutive scoreless innings during that span dating back to Sept. 6, 2010 ... Arizona was held without an extra-base hit. The D'backs had registered at least one extra-base hit in a major league-best 79 straight games.