LOS ANGELES – From his vantage point behind the plate, Giants catcher Buster Posey said he wasn't sure if Clayton Kershaw's hit had enough oomph to clear the fence in the deepest part of Dodger Stadium. Nor was George Kontos, who threw the two-seam fastball to start the eighth inning that Kershaw – the Dodgers' ace who had one extra-base hit in five seasons in the majors – crushed to straightaway center field.

"I think the ball just ran back to the middle a little bit – and he was all in," Posey said of Kershaw. "I think he was swinging pretty much no matter what."

Giants center fielder Angel Pagan gave chase briefly before turning and watching the ball sail over the fence as the Opening Day crowd at Dodger Stadium erupted. With his first career home run, Kershaw gave himself all the offense he needed as he continued his mastery of the Giants with a complete-game shutout in the Dodgers' 4-0 win Monday.

The defending World Series champions had just four hits – two singles apiece by Angel Pagan and Pablo Sandoval – against Kershaw, who according to a Major League Baseball tweet became the second pitcher since 1921 to throw a complete game and hit a home run on Opening Day. The other was Bob Lemon in 1953 with Cleveland. Kershaw also is the first Dodgers pitcher to homer on Opening Day since Don Drysdale in 1965.

The Dodgers added three more runs in the eighth to give the left-hander a cushion when he came out for the ninth. He needed 94 pitches to complete the game.

"He's been tough on us," Giants manager Bruce Bochy said. "He's one of the best pitchers in the game. He was on top of his game today, and to go out there and go nine the first game, that's pretty impressive."

While some of the hitters wearing Giants jerseys have changed since Kershaw entered the league in 2008, his treatment of them has not. Kershaw began the game with the lowest all-time ERA of any pitcher who has thrown at least 50 innings against the Giants – and he lowered it to 1.28 Monday. Three of his six career shutouts are against the Giants.

Sandoval, who singled with two outs in the first and advanced to second on a wild pitch, was the only Giant to reach scoring position. Aside from Pagan and Sandoval, the Giants were 0 for 22 against Kershaw with seven strikeouts, including an 0-for-4 day by Marco Scutaro, whose 20-game hitting streak dating to last season was snapped.

Giants right-hander Matt Cain matched zeroes with Kershaw for six innings.

When Cain departed, the starters had combined for 13 strikeouts – eight by Cain – and only seven balls allowed out of the infield. Kontos pitched a scoreless seventh and came out for the eighth with Kershaw, who had struck out in his first two at-bats, leading off.

Kontos said he threw "a two-seamer that just flattened out, and (Kershaw) just put a good swing on it. He's a big, strong guy. So you make a mistake, he's going to put a good swing on it.

"This is the big leagues," Kontos said. "Guys are going to do that to you."

Bochy said he liked how Kontos was throwing and didn't consider bringing in a left-hander specifically to face Kershaw. The next four Dodgers hitters reached base, and Los Angeles scored three runs on a wild pitch and two groundouts.

It broke open what had been a quick-moving duel between Kershaw and Cain, making his first Opening Day start. Cain threw 29 pitches in the first inning but needed just 44 to get through the next four and, after allowing a leadoff double in the sixth, escaped the jam by striking out left-handed sluggers Adrian Gonzalez and Andre Ethier – both looking.

Posey said it may well be a sign of things to come when these teams and their pitching staffs meet.

"I feel like there'll probably be a lot of tight games," Posey said. "I think that will probably be the theme with us."

Call The Bee's Matt Kawahara, (916) 321-1015. Read his Bay Area Baseball blog at blogs.sacbee.com/bay-area-baseball/. Follow him on Twitter @matthewkawahara.

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