Looking for a season-high fourth straight victory, the Padres can accomplish that feat by handing the visiting Giants a fifth consecutive loss Sunday.San Diego (8-15) totaled two runs and was shut out twice while being swept at San Francisco (13-11) last weekend, but has scored 10 in the first two games of this set and rallied from a 5-0 deficit to win 8-7 in 12 innings Saturday. Yonder Alonso scored the winning run when San Francisco second baseman Marco Scutaro couldn't come up with Nick Hundley's grounder."It gives us great momentum, a chance to sweep," said Hundley, who is batting .342 in 10 homes games this season. "We've got to get another one (Sunday)."The Padres, who last swept the Giants both home and away in 2010, have scored 12 runs during a three-game winning streak that followed a five-game slide where it totaled six runs.Alonso and Kyle Blanks each had three hits and combined to drive in three runs Saturday for the Padres, who scored six times in the fourth inning and tied the game with a run in the seventh."Wins like this give you life," said Alonso, who had three doubles. "They give you an opportunity to build some momentum and create a string of positive results."Alonso is 7 for 19 (.368) with four RBIs in five games.The Padres hope scheduled starter Jason Marquis (1-2, 4.63 ERA) can bounce back after he allowed seven runs and walked four in 4 2/3 innings of a 7-1 loss to Milwaukee on Monday. Seven of the 15 runs the right-hander has yielded this season have come in the first inning."I've been battling for a while," Marquis told the Padres' official website. "When you throw balls out over the middle of the plate with not much on them, that's obviously what happens. I've just got to focus on getting better."I just don't feel comfortable on the mound."Marquis, however, is 6-5 with a 2.82 ERA in 14 starts versus San Francisco.Pablo Sandoval is batting .353 (6 for 17) with two home runs against Marquis. The slugger had three hits Saturday after he went 0 for 9 in the previous two contests for the Giants, who have dropped three straight one-run games.San Francisco's Barry Zito was charged with five unearned runs in the San Diego fourth."He just couldn't get the last out in the fourth," manager Bruce Bochy said. "That's what killed us."Scheduled San Francisco starter Ryan Vogelsong (1-1, 5.68) went 3-1 with a 2.05 ERA against the Padres last season. He's yielded a run and five hits over six innings in each of his last two outings versus San Diego.The right-hander allowed one home run against the Padres in 2012, but has served up four in his last three starts overall. He gave up two solo shots and two other runs in seven innings while not factoring in the decision of a 5-4 win over Arizona on Monday.San Diego's Will Venable is 0 for 9 in the last three games but 6 for 10 against Vogelsong.