Updated

Chase Headley hit a two-run homer and drove in three, as the San Diego Padres defeated the San Francisco Giants, 7-3, on Saturday.

Jesus Guzman added a solo home run and an RBI double for the Padres, who halted a three-game slide.

Eric Stults (8-3) allowed six hits -- including Hunter Pence's three-run homer in the first -- with three walks and five strikeouts over six innings in the win.

"I think any time you let the other team know that you're rattled or flustered, they kind of feed off that," Stults said. "So after giving up three in the first, I was just trying to take it one hitter at a time and work as deep as I could."

Buster Posey had a pair of hits for the Giants, who have already clinched the NL West title. They are currently four games behind the Washington Nationals for the best record in the NL.

Madison Bumgarner (16-11) lasted just four innings and gave up five runs -- four earned -- in the loss.

"He was a little off and it effected his command. He was battling himself out there," Giants manager Bruce Bochy said about Bumgarner. "He was out of synch out there at times and he had trouble getting the ball where he wanted."

Pence followed a walk by Pablo Sandoval and a Posey single with a two-out blast in the first, but he grounded into a fielder's choice with the bases loaded to end the fifth.

Chris Denorfia started the home first with a triple and Logan Forsythe drew a walk before Headley pushed across a run with a fielder's choice groundout.

Headley then stole second base, moved to third on an error by Marco Scutaro and crossed the plate on Yasmani Grandal's sacrifice fly.

The third baseman then put the Padres on top for good in the third when he followed Denorfia's leadoff single with his 30th homer of the season. Guzman belted a solo shot later in the frame for a 5-3 lead.

Grandal added an RBI single off Brad Penny in the fifth and Guzman sealed the final result with a run-scoring double later in the inning.

The rubber match of this three-game series is set for Sunday.

Game Notes

Stults has won seven of his last eight decisions. He improved to 4-2 in 11 career games -- nine starts -- against the Giants ... San Francisco went 1- for-4 with runners in scoring position and left six on base.