SAN DIEGO -- Craig Stammen says it's a "privilege" to be called upon to enter a game with the bases loaded.

"It's one of the best feelings in baseball when you're walking off the field after getting out of one of those jams," the San Diego Padres' reliever said.

Stammen was feeling great Wednesday night when he came on to work out of a bases-loaded, one-out jam while protecting a one-run lead against the San Francisco Giants.

Stammen's effort became a key moment as the Padres beat the Giants 5-0 in the rubber match of a three-game series at Petco Park.

Left-handed starting pitcher Travis Wood and Jose Pirela homered for the Padres, and Jabari Blash amassed two singles, two walks, a run and an RBI.

However, it was the Padres' bullpen, starting with Stammen, that dominated the game. Five San Diego pitchers combined on a six-hit shutout -- the Padres' ninth shutout of the season. Relievers Stammen, Buddy Baumann, Kirby Yates and closer Brad Hand retired 14 of the 16 Giants they faced.

No one got bigger outs than Stammen, who faced a bases-loaded situation for the seventh time this season. He has worked out of the situation six times, with the only failure coming on an error.

"Stammen has done it time and time again," Padres manager Andy Green said. "It's great to have a weapon like that."

Stammen, who was credited with the win, said, "The only thing I'm concentrating on is throwing strikes."

Stammen came on after the Giants loaded the bases against Wood with one out in the fifth.

Wood had homered with one out in the third to give the Padres a 1-0 lead. The 387-foot drive to left off Giants starter Ty Blach (8-11) was the 10th of Wood's career, not counting a postseason homer he hit last season against the Giants while with the Chicago Cubs.

Wood struggled on the mound Wednesday. In 4 1/3 innings, he allowed six hits and four walks and departed with the bases loaded with his pitch count at 97.

Stammen entered and struck out Hunter Pence, then retired Nick Hundley on a grounder to second to end the threat.

"He got the big strikeout with one out and got out of the inning," Giants manager Bruce Bochy said. "That's what wins games for you, coming through in situations like that. The Padres came through when given an opportunity in the sixth. We didn't capitalize."

Through the first five innings, the Giants left eight runners on base, including five in scoring position. They grounded into two double plays in the first three innings and went 0-for-8 with runners in scoring position in that span. Then the Padres' bullpen took over.

Stammen retired all five hitters he faced. Baumann struck out two in a perfect seventh. After Yates sandwiched two walks around a pair of strikeouts, Hand retired all four hitters he faced for his 14th save of the season and his second in as many nights.

The Padres defeated the Giants for the ninth time in the last 12 meetings. San Diego is 19-7 against San Francisco since the Giants defeated the Padres nine straight times to open the 2016 season.

After Stammen retired the Giants in order on three fly balls to left fielder Pirela in the sixth, the Padres scored three times in their half of the inning, against Blach and reliever Kyle Crick, to turn their 1-0 lead into a four-run lead.

Pirela made it 2-0 with his ninth homer, the 384-foot drive off Blach landing on the second balcony of the Western Metal Supply Co. building in left.

Wil Myers followed with a double. After he moved to third on an infield out, Crick replaced Blach and immediately threw a wild pitch, allowing Myers to score to make it 3-0. Crick then walked Blash, who came around on singles by Cory Spangenberg and Austin Hedges -- the catcher getting his 50th RBI of the season.

A pair of infield errors and a one-out RBI single by Blash upped the Padres' lead to 5-0 in the eighth.

Blach allowed three runs on five hits in 5 2/3 innings.

NOTES: Padres SS Erick Aybar, who has been on the disabled list since July 23 with a fracture in his right foot, is headed for the rookie-level Arizona League for a few days before possibly rejoining the Padres as a September call-up. ... Giants C Buster Posey missed a third consecutive game with a bone bruise and inflammation to his left thumb. He is expected to return to the lineup Thursday as San Francisco opens a four-game homestand against the St. Louis Cardinals. ... RHP Johnny Cueto (flexor tendon strain) threw a bullpen session Wednesday, and he could return to the Giants' rotation this weekend. ... Pitchers had four of the game's first eight hits. Giants LHP Ty Blach was 2-for-2, Padres LHP Travis Wood homered, and RHP Craig Stammen singled.