SAN FRANCISCO -- With Clayton Kershaw having thrown his final pitch to end the eighth inning in a 2-2 tie, the San Francisco Giants seemed to have the Los Angeles Dodgers right where they wanted them late Friday night.

Until Justin Turner stepped to the plate in the ninth, that is.

Turner lined Santiago Casilla's fourth pitch for a tie-breaking home run, enabling the Dodgers to edge the Giants 3-2 in the opener of a three-game series between the top two teams in the National League West.

"Get on base," Turner said of his approach to the difference-making at-bat. "I've got Gonzo (Adrian Gonzalez) and Trayce (Thompson) behind me. The only goal there is get on base to let them do what they do.

Kershaw allowed five hits over eight innings, striking out 13, for his seventh consecutive victory, overcoming a Matt Duffy homer to win for the 10th time in 13 career decisions at AT&T Park.

The triumph allowed the Dodgers (33-29) to move within three games of the Giants (36-26) in the NL West. The teams have played to a 4-4 tie in the season series.

"Everyone in the clubhouse knows how important this win was," Dodgers manager Dave Roberts insisted. "We're chasing these guys."

Casilla (1-2) opened the ninth inning in relief of Johnny Cueto, who matched Kershaw pitch-for-pitch after getting burned by a disputed balk call in a two-run Dodgers first inning.

Closer Kenley Jansen pitched around a two-out double by Brandon Belt and a walk to pinch-hitter Gregor Blanco in the ninth to record his 17th save, striking out Brandon Crawford on a full count to end it.

"It's a tough one to lose," Giants manager Bruce Bochy lamented. "A home run in the ninth got us, but Cueto did a super job."

Kershaw (9-1), who hasn't lost since April 26, did not walk a batter in his eight innings. He struck out the side in the second inning and fanned at least two in three other innings.

His 13 strikeouts gave him 82 against just three walks in his eight starts since May 1.

"It was a fun game to be a part of," Kershaw claimed. "When you're pitching against Cueto, you know it's going to be like this."

The balk occurred with runners on second and third with no outs in the first when Cueto, who often mixes up the speed of his delivery, put one too many a twitch into his wind-up on a pitch to Turner. First-base umpire Bill Welke awarded Chase Utley home plate.

"When you pitch from the wind-up, you have to deliver the ball without interruption or alteration," Welke explained afterward. "When he rolled back, he came to a complete stop and then he shook forward and back, forward and back with his shoulders and his foot was moving."

The balk also advanced Corey Seager to third base, from where he made it 2-0 one batter later when Gonzalez singled.

The Dodgers totaled three hits in the first, but that was all they got off Cueto in his eight innings. He allowed only one more baserunner -- hitting Utley with a pitch for a second time -- after the first inning.

Cueto struck out eight and did not walk a batter. Despite a hit batsman, a wild pitch and a balk, both runs off him in the first inning were earned.

But four batters after Cueto handed off the ball to the bullpen, the game was lost.

"I will admit," Bochy said, "we need to get a little better there late in the ballgame."

Duffy's homer, a solo shot, came in the bottom of the first, and the Giants rallied to tie the game off Kershaw in the sixth.

Buster Posey's two-out double to the base of the fence in left-center field scored Joe Panik, who had singled, to produce the 2-2 tie.

The win came in the Dodgers' 150th game at AT&T Park. There record in those games is now 73-77.

The Giants, who have gone just 6-7 in their last 13 games, out-hit the Dodgers 6-5.

NOTES: The Giants (INF Ehire Adrianza, LHP Madison Bumgarner and 3B Matt Duffy) have hit three of the five home runs allowed by LHP Clayton Kershaw this season. ... The last time two starters with at least eight wins and ERAs under 2.25 squared off before the All-Star break was RHP Jake Peavy -- then of the San Diego Padres -- facing Dodgers RHP Brad Penny on June 30, 2007. ... The Dodgers have scheduled RHP Brandon McCarthy (right elbow surgery) and RF Yasiel Puig (strained left hamstring) for rehab assignments at Class A Rancho Cucamonga on Saturday and Monday, respectively. ... Before the game, the Giants placed INF/OF Kelby Tomlinson (sprained left thumb) on the 15-day disabled list and promoted INF Ramiro Pena from Triple-A Sacramento. RHP Sergio Romo (strained right flexor) was moved from the 15- to the 60-day DL to create a roster spot for Pena ... The Giants plan to send LF Angel Pagan (strained left hamstring) on an injury-rehab assignment at Triple-A Sacramento on Saturday, with hopes he could be reinstated from the DL sometime next week.