SAN DIEGO -- The San Diego Padres rocked the San Francisco Giants and Madison Bumgarner in Saturday night's 10-2 win.

This time, James Shields got the better of Bumgarner, unlike in the last World Series.

Bumgarner beat Shields in Games 1 and 5 when Shields was pitching for the Royals.

But San Diego chased Bumgarner (1-1) after three innings.

Shields (1-0), who signed a $75 million contract with the Padres as free agent, pitched seven innings, allowing one run and three hits.

The Padres, who had 20 hits off three Giants pitchers, extended their advantage to 8-1 when scoring three runs in the sixth inning, this time off Ryan Vogelsong.

Shields, who was making his Petco Park debut as a Padre, even got into the act with a crisp single to right. The RBIs came from the Padres' revamped outfield -- center fielder Wil Myers, right fielder Matt Kemp and left fielder Justin Upton.

The Giants got their first hitters on base in the sixth and seventh innings. But Shields, who struck out seven and walked one with a hit batter, was able to wiggle from the potential jams.

Kemp led the Padres with four hits and an RBI. Third baseman Wil Middlebrooks had three hits and two RBIs. Yangervis Solarte had three hits and an RBI. Upton, and Norris each had two hits. Myers also contributed two RBIs.

Giants third baseman Joaquin Arias led off the fourth with his first home run of the season, slicing the deficit to 5-1.

San Diego scored three runs in third inning when it sent eight batters to the plate. After Solarte and Upton singled, catcher Derek Norris, Middlebrooks and second baseman Jedd Gyorko contributed consecutive RBI singles for a 5-0 cushion.

Bumgarner, who allowed 10 hits and five runs in three innings, didn't return for the fourth and was relieved by Vogelsong.

The Padres committed their second error in three innings when shortstop Clint Barmes' bad throw to first allowed Nori Aoki to reach in the third. But Shields sandwiched ground outs by second baseman Joe Panik and center fielder Angel Pagan between a nifty catch by Kemp.

After snapping a 22-inning scoreless streak on Friday, the Padres got busy quickly.

In the first, Upton's RBI single drove in Kemp after his two-out double. For Upton, it was his 10th hit in 26 career at-bats against Bumgarner.

Norris and Middlebooks followed with singles, with Middlebrooks' hit chasing home Upton for a 2-0 Padres lead.

The Giants wasted an opportunity in the first after Panik's one-out single. Catcher Buster Posey lifted a popup to Solarte at first base and he looked like someone making his first major-league debut at that position.

Solarte had the ball hit off his glove for an error and Panik advanced to third. But Shields got Casey McGehee to fly out to center to end the inning. McGehee left the game after the at-bat with a strained left knee.

NOTES: Padres INF Yangervis Solarte got his first major-league start at first base on Saturday. Solarte, a switch-hitter who has seen time at second base, got the nod over the left-handed Yonder Alonso against LHP Madison Bumgarner. ... LHP Frank Garces isn't being pigeon-holed as a lefty specialist, manager Bud Black said. ... Recently recalled RHP Brandon Maurer can fill either a long or short role out of the bullpen, Black said. ... Giants 1B Brandon Belt (strained groin) continues to improve and is available for pinch-hitting duties. ... Manager Bruce Bochy said it has been a challenging series. "I'm having a hard time keeping up with the game times," he said. Games have started at 3:40 pm, 7:10 p.m, 5:40 pm and on Sunday, at 1:10 p.m.