SAN FRANCISCO -- The Giants’ offense hasn’t enjoyed much of a home-field advantage at Oracle Park this season, a trend that continued in a 4-2 loss to the Pirates on Thursday afternoon.

After dropping three of four games to the Bucs, the Giants have now lost nine of their last 11 home games dating to Aug. 14. Overall, they are 31-41 (.431) at Oracle Park this year, their lowest home winning percentage in a season since their waterfront ballpark opened in 2000.

“I think more than anything, we have a tough time scoring here,” Giants manager Bruce Bochy said. “I think it’s been the offense as much as anything. We’ve had some pretty good days on the road, but here at home, for some reason, we just have a hard time getting it going.”

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San Francisco was held scoreless over the first five innings by Pittsburgh right-hander Joe Musgrove, who allowed only four hits while striking out seven. After Musgrove left the game, the Giants finally got on the board in the sixth on Evan Longoria’s 19th home run of the season, a two-run shot off reliever Yacksel Rios that cut the deficit to 3-2.

But the Pirates got the run back in the seventh when Jacob Stallings crushed a leadoff homer off veteran right-hander Jeff Samardzija, who was charged with his 12th loss of the season after giving up four runs over 6 1/3 innings.

The Giants threatened in the ninth, putting runners on the corners with no outs, but Bucs closer Felipe Vazquez struck out Austin Slater and Mike Yastrzemski and then coaxed a groundout from Buster Posey to end the game.

Thursday’s loss kept Bochy’s career win total at 1,996, meaning he will not get a chance to reach 2,000 during this homestand. The earliest Bochy can reach the milestone will be Tuesday, when San Francisco begins a six-game road trip to Boston and Atlanta.

Though Oracle Park has long been known for suppressing offense, the Giants’ offensive home-road splits this season have been striking. San Francisco is averaging only 3.5 runs per game at home (249 runs over 72 games), and the team entered Thursday batting .229 with a .654 OPS at Oracle Park.

By contrast, the Giants are averaging 5.1 runs per game on the road (380 runs over 75 games), where they’ve gone 39-36 this season. Away from home, they’re batting .249 with a .743 OPS. Kevin Pillar is San Francisco’s only hitter to reach double digits in home runs at Oracle Park this season (11), but four -- Longoria (14), Yastrzemski (12), Brandon Belt (11) and Pillar (10) -- have done so on the road.

“You want to win at home,” Samardzija said. “It’s definitely great to have that advantage of playing at home and teams know it’s a tough place to play. Obviously, we kind of need to take that road mentality and kind of apply it to here next year. It’s definitely a little weird.”

The Giants’ offensive woes at home should only spur more debate in the front office about whether it’s finally time to move in the fences at Oracle Park, a topic that has received renewed attention this year.

When Belt sent a deep drive to right-center field with two outs in the first, he came away with a 390-foot triple and was left stranded when Longoria struck out to end the inning. Next year, he could be rewarded with a home run on a similar hit, especially if the Giants decide to eliminate Triples Alley and move the bullpen mounds to a safer location on the field.

Davis exits with injury

Rookie outfielder Jaylin Davis exited the game in the sixth inning after he was struck on the left wrist by a 97-mph fastball from Rios. Davis grimaced in pain and received attention from Giants trainer Anthony Reyes before walking off the field. Davis was replaced on the basepaths by Joey Rickard, who stayed in the game to play left field.

Bochy said after the game that X-rays came back negative on Davis, who is considered day to day with a bruised left wrist.

“I can’t tell you how long he’ll be out,” Bochy said. “I’m sure he’ll be pretty sore tomorrow. It caught him pretty good.”

Davis, who was acquired from Minnesota as part of the Sam Dyson trade, is 3-for-21 over his first seven games with San Francisco.