SAN DIEGO (AP) -- The San Diego Padres have not always pitched tough in tight situations this season. The last two games, however, the Padres have been resolute.
Chris Denorfia hit a go-ahead RBI single in the seventh inning and San Diego's bullpen was stingy with runners on base, leading the Padres to a 3-2 victory over the San Francisco Giants on Tuesday night.
San Diego held the Giants to just three hits in 15 at-bats with runners in scoring position and stranded 11 base runners. In their 4-1 win on Monday, the Padres left nine San Francisco runners stranded, holding the Giants to 1 for 7 with runners in scoring position.
''We've been off the mark for most of the year,'' Padres manager Bud Black said. ''But the last couple of (games), we've been able to make the pitches when we needed to.''
San Francisco threatened in each of the last four innings, but relievers Tim Stauffer (3-1), Luke Gregerson and closer Huston Street all pitched out of trouble.
''It's been an issue for a while,'' San Francisco manager Bruce Bochy said. ''It reared its head again.''
Giants catcher Buster Posey was pinch hit for in the seventh after he ripped a nail on the ring finger of his right hand on a wild pitch thrown by Madison Bumgarner in the sixth inning.
Posey shook his right hand after Bumgarner's pitch in the dirt and spent a couple of minutes being attended to by a trainer before he stayed in the game and completed the inning.
''(The pitch) may have hit the lip of home plate,'' said Posey, the reigning NL MVP. ''I can throw the ball fine, but I really didn't try to grip the bat.''
Stauffer relieved starter Robbie Erlin in the sixth with one out and runners on first and second, nursing a 2-1 lead. Although Stauffer allowed an RBI single to Joaquin Arias, he escaped further damage by striking out two straight batters to end the inning.
The right-hander then allowed a leadoff triple by Angel Pagan in the seventh before retiring three straight.
''Just trying to make some pitches and get one guy at a time and try not to throw anything out over the plate that they can flip to the outfield,'' Stauffer said. ''Luckily, I was able to get a couple of popups and a strikeout. I think it was a momentum shift that kind of helped.''
Said Erlin: ''I kind of left him a tough spot there. He minimized the damage for me and did a great job.''
Gregerson allowed consecutive two-out singles in the eighth before striking out pinch hitter Roger Kieschnick. Street gave up Brandon Belt's two-out double before getting Hector Sanchez to ground out to end the game.
Nick Hundley drew a leadoff walk in the seventh from rookie reliever Jake Dunning, who was called up earlier in the day from Triple-A Fresno. Ronnie Cedeno followed with a single to send Hundley to third and bring on reliever Javier Lopez.
Denorfia lined a 1-2 pitch to left for the single that broke a 2-all tie.
Dunning (0-2), who made his major league debut in June, took the loss. Stauffer threw 1 2-3 innings of shutout ball.
Street pitched the ninth for his 26th save in 27 chances.
Defending World Series champion San Francisco (61-77) dropped into last place in the NL West, one game behind San Diego.
Pagan had a single, double and triple heading into his final at-bat in the ninth when he struck out.
San Diego took a 2-0 lead in the fifth following a leadoff double by Kyle Blanks and Hundley's one-out double. After Cedeno was walked intentionally, Erlin drove in the second run with a bloop single. It was Erlin's first major league hit and RBI.
The Giants tied it in the sixth. After consecutive singles by Belt and Posey to start the inning, Pedro Sandoval and Arias followed with consecutive RBI singles with one out.
Bumgarner lasted six innings and gave up two runs and five hits with six strikeouts and two walks.
Since the All-Star break, Bumgarner has just one winning decision in nine starts. The left-hander is 1-4 with a 2.67 ERA in that span.
Erlin allowed two runs and six hits in 5 1-3 innings. The left-hander struck out five and walked two.
NOTES: San Francisco RHP Heath Hembree made his major league debut with one inning of perfect relief. ... Padres rookie RHP Burch Smith will start on Friday against Colorado. Smith, who was recalled from Triple-A Tucson on Monday, is 0-1 with an 18.41 ERA in three starts earlier this season with San Diego . ... Giants RHP Tim Lincecum (8-13, 4.38 ERA) opposes Padres LHP Eric Stults (8-12, 3.81) in the series finale Wednesday.