SAN FRANCISCO -- After manager Bruce Bochy labeled Saturday's 5-4, 10-inning victory over the Los Angeles Dodgers his club's best win of the year, San Francisco Giants rookie Chris Stratton could do his skipper one better.

It was the greatest moment of his career.

"They picked me up big-time," a thrilled Stratton gushed of his Giants teammates, especially Buster Posey, who capped a two-run rally in the bottom of the 10th with a walk-off single to center field.

The right-hander's first career win appeared headed for the loss column just moments earlier, when he served up a leadoff home run to Adrian Gonzalez in the top of the 10th.

But handed a 4-3 lead and shooting for an 18th save, Dodgers closer Kenley Jansen (2-2) ran into trouble after retiring Jarrett Parker on a popup to start the inning.

Denard Span got the rally going with a double into the right-field corner, after which Joe Panik tied the game with a single to left-center.

After Brandon Belt blooped a single to right, Posey singled up the middle, scoring Panik with the game-winner.

"They saved me," assured Stratton (1-0), the ninth Giants pitcher who had just two innings of previous major-league experience. "Getting a loss is always the worst, especially on this stage, against your rivals.

"It's a huge win, especially getting (two runs) off Jansen. He doesn't give up runs."

The dramatic win allowed the Giants to even the three-game series at a victory apiece after the Dodgers won 3-2 on Friday night on a tiebreaking homer by Justin Turner in the ninth inning.

The Giants (37-26) picked up the game in the standings that they lost to the Dodgers (33-30) in the series opener and re-opened a four-game advantage atop the National League West.

"I'd say so," Bochy responded when asked if the club's major league-leading sixth walk-off win was the Giants' biggest of the season. "After (Friday) night, and they get a home run in extra innings ... to come back off one of the better closers in the game ...

"Yeah, I'd put that near the top if not at the top."

The Dodgers took a big step toward what could have been their second consecutive one-run win when Gonzalez hit Stratton's second pitch over the left-field fence for his sixth homer of the season.

But Stratton, pitching for just the third time in the majors, retired three of the next four guys he faced to keep the Giants within one, setting up the dramatics in the bottom of the inning.

"He could have gotten rattled," Bochy noted. "But he kept them at one run and gave us a chance.

"Then we got the right guy (Posey) up there."

The walk-off was the fourth of Posey's career.

Panik had two hits and Matt Duffy two RBIs for the Giants, who improved to 23-13 against NL West competition.

The Giants have beaten the Dodgers in 12 of their last 16 meetings at AT&T Park.

Gonzalez, Turner and Trayce Thompson had two hits apiece for the Dodgers, who out-hit the Giants 11-7 but went 1-for-9 with runners in scoring position and stranded 10.

"It felt like we had one taken away," Dodgers manager Dave Roberts lamented. "It's a team we're chasing and we had a chance to gain ground."

The Dodgers rallied from 2-0 and 3-2 deficits, drawing even at 3-3 in the seventh in an inning in which the Giants used five relievers.

Chase Utley, who had the inning's only hit, scored the tying run when Giants right-hander Cory Guerrin issued a two-out, bases-loaded walk to Thompson.

But befitting their evening, the Dodgers left the bases loaded.

The blown save was just Jansen's third of the season.

"No one is going to lose faith because of what happened today," Thompson assured. "We'll come back (Sunday) and try to get the series."

Neither starting pitcher got a decision.

Dodgers left-hander Scott Kazmir left two batters into the bottom of the sixth, during which the Giants took their 3-2 lead.

Panik led off the inning with a single and moved up a base when Kazmir walked Belt, the final batter he faced.

The Dodgers then got only one out apiece on two potential double play grounders induced by reliever Louis Coleman, with Panik advancing a base on each and scoring the go-ahead run.

Kazmir allowed three runs and three hits in his five-plus innings. He struck out three.

The Giants' first two runs off Kazmir came in the first inning on RBI singles by Duffy and Brandon Crawford.

Giants starter Jeff Samardzija couldn't hold the 2-0 lead, allowing a run in the third on an RBI single by Yasmani Grandal and one in the fifth on an RBI double by Gonzalez.

The right-hander was pulled after Gonzalez's hit, and right-hander George Kontos struck out Thompson to keep the game tied.

Samardzija gave up two runs in a season-low 4 2/3 innings. He allowed seven hits, walked two and struck out three.

NOTES: Golden State Warriors coach Steve Kerr and guard Klay Thompson attended the game. Thompson's brother, RF Trayce Thompson, batted fifth for the Dodgers. ... The game featured 15 pitchers who issued 13 walks. ... The Giants made a significant change in their batting order, moving 1B Brandon Belt to third and demoting 3B Matt Duffy, who homered Friday night off LHP Clayton Kershaw, to fifth. ... Giants manager Bruce Bochy announced before the game that RHP Matt Cain (strained right hamstring) will be activated off the 15-day disabled list on Monday and start the series opener that night against the Milwaukee Brewers. ... Dodgers LHP Hyun-Jin Ryu (torn labrum) has been scheduled to begin an injury-rehab stint in the minors Sunday at Single-A Rancho Cucamonga, Ryu hasn't pitched a major league game since Sept. 12, 2014. ... The Dodgers released INF/OF Jose Tabata, who had been playing at Triple-A Oklahoma City, off their 40-man roster. Tabata, who had been hitting .244 in the minors this season, had a guaranteed $4.5 million contract for 2016.