SAN DIEGO -- The San Diego Padres, who had the second-worst record in the major leagues as of Wednesday, are suddenly hot.
One weekend after getting swept in San Francisco, the Padres returned the favor this weekend, completing a three-game sweep of the Giants with a 6-4 victory Sunday at Petco Park.
"Can't explain it; wish I could," Padres manager Bud Black said. "Baseball's a game a lot of times that's unpredictable. You never know how a month's going to play out, or let alone a week. It's good to see we were able to come out today and get to (Ryan) Vogelsong, and Jason (Marquis) did his thing. Wish I could explain it."
The Padres (9-15) have won four in a row. They were fueled Sunday by three home runs on a sunny day that saw the ball carry well.
Chase Headley hit a solo homer in the first inning, Nick Hundley hit a two-run shot in the second, and Alexi Amarista added a two-run homer in the sixth.
The Giants (13-12) were stymied by starter Marquis (2-2). The right-hander went 6 2/3 innings, allowing two runs on six hits with three strikeouts and four walks.
A wobbly Vogelsong (1-2) absorbed the loss, as he was touched for six runs (five earned) on eight hits in five innings.
"It's a battle from the start for Vogey," Giants manager Bruce Bochy said. "He didn't have good stuff or command. It was just a case where he was battling without his good stuff; he made some mistakes. The ball was up quite a bit, and they didn't miss 'em."
For the defending world champion Giants, this season continues to be a struggle. They have lost five in a row and eight of their past 12 games, and they have a six-game road losing streak.
"You look at the last five games, and they very easily could have gone our way," Giants catcher Buster Posey said. "We're playing some tight games, so we have to keep on grinding and we will be all right."
Headley, whose second homer of the season went 411 feet to center field, finished 3-for-3 with a walk.
"It's great to see some guys hit some home runs today, and we executed the little things, we're making plays defensively and got a couple of big hits," Headley said. "Our pitching did a nice job for us. Not a huge difference, but enough to swing the series."
Hundley finished 2-for-4. The catcher, who struggled last year before landing on the disabled list with a knee injury, continues to be one of the Padres' most consistent bats with a .314 average.
Amarista went 2-for-3, drew a walk and scored three runs. His homer gave San Diego a 5-1 lead.
After Marquis exited in the seventh with a 6-2 lead, Brad Brach got the last out of the inning. However, Brach gave up a two-run homer to Posey in the eighth, cutting the Padres' lead in half.
Luke Gregerson entered and got all three outs in the eighth, and Huston Street pitched a scoreless ninth for his five save of the season.
"We haven't been playing so well," Bochy said. "We've been making mistakes that have hurt us in this little streak we are in. Guys could use a little break, too; it's a tough series. You're going to have them. You don't like 'em, but we're going to deal with it."
The Padres, meanwhile, finally are appear to be finding their form.
"We're definitely playing a lot better baseball right now," said right fielder Chris Denorfia, who made a tumbling catch to preserve the Padres' lead in the eighth. "Our pitching's been outstanding the last week, maybe more. Our hitting's coming around. We've got Chase and Carlos (Quentin) back in the lineup, so we're starting to be the team we knew we could be coming out of spring training."
NOTES: Alexi Amarista's two-run home run in the fourth traveled but 369 feet and was the first one by the Padres to clear the new fence in right field. The previous three to take advantage of the fresh dimensions were all hit by opponents. ... The Giants have struggled away from AT&T Park, losing eight of 13 road games. ... San Diego has stolen 11 straight bases without getting caught. ... The Padres' road trip, which begins Monday against the Cubs, is brief. Chicago, where the Padres will play four games, is the only stop, with the Padres returning to San Diego on Friday for the opener of a three-game series against the Diamondbacks. ... The Giants will visit Arizona for three games starting Monday, then return home Friday for a weekend series against the Dodgers. ... The Padres last swept the Giants at home in April 2010.