SAN DIEGO -- On Monday, Jeff Samardzija was the Jeff Samardzija the San Francisco Giants hoped they got when he signed a five-year free agent contract in December 2015.

Although Samardzija has struggled during his Giants stint, he delivered one of the better games of his career Monday against the Padres. He threw his fourth career shutout and first since 2015, and Brandon Crawford and Joe Panik homered as San Francisco beat San Diego 3-0 on Monday.

Samardzija (9-12) allowed only three singles and struck out five. He didn't issue a walk.

"He really was locked in with everything," Giants manager Bruce Bochy said. "Great focus out there with every pitch."

After Wil Myers' infield hit in the second, Samardzija retired seven straight. Following Yangervis Solarte's infield single in the fifth, he sat down 11 in a row.

Samardzija, who pitched his ninth career complete game, had struggled against the Padres this season, pitching to a 7.27 ERA and 0-1 mark in three previous starts. However, the right-hander dominated from the outset as the Padres offered little resistance in losing their fourth consecutive game.

"I kind of owed these guys," Samardzija said. "It was just one of those things, take a little pride in yourself, going out there and getting after a team that had your number."

The Giants won on the road for just the fourth time in 17 games. They beat the Padres for the third time in the past 10 meetings.

Jhoulys Chacin (11-10) absorbed a rare loss at Petco Park. He worked five innings, surrendering one run and two hits. He struck out three and walked four.

"I wasn't throwing my slider very well, and I was battling with my fastball," Chacin said. "When you throw over 90 pitches in five innings, you don't get a chance to go back out (for) the sixth."

It was only Chacin's third home loss in 10 decisions this year. And it was his first loss to the Giants this season after he went 3-0 against them.

Crawford's 12th homer sent the Giants ahead 1-0 in the fourth. Chacin tried to sneak a 92 mph, full-count fastball past Crawford, who sent it over the center field fence, 411 feet away.

Panik's two-run homer that hit the right field foul pole in the eighth off reliever Phil Maton gave Samardzija some breathing room, although he didn't need it. Panik's long fly came with Crawford aboard after his second hit, a single.

"The difference tonight was (Samardzija) being able to get ahead with his off-speed pitches," Padres manager Andy Green said. "He commanded all his pitches. He pitched well, although we didn't do much to put pressure on him. We had a lot of empty at-bats."

Chacin, who hit four batters and walked three in his previous outing, struggled with his command in the second inning Monday. Denard Span and Jarrett Parker drew bases on balls, sandwiched around a single by Hunter Pence, to load the bases with two outs.

However, Pablo Sandoval's line drive to third baseman Cory Spangenberg ended the threat.

Pence finished with two hits.

NOTES: Giants C Buster Posey (thumb) was out of the lineup, and he could miss several games. The team was awaiting the results of an MRI exam. ... Giants RHP Johnny Cueto (flexor) will throw a bullpen session on Tuesday or Wednesday. ... Padres C Hector Sanchez, who entered the game hitting .500 (6-for-12) with three homers against San Francisco RHP Jeff Samardzija, went 0-for-3 Monday. ... Padres RHP Miguel Diaz (forearm) will make one more rehab appearance for Triple-A El Paso, and then he could rejoin the parent club.