WASHINGTON (AP) -- The San Francisco Giants created numerous scoring chances against the Washington Nationals on Tuesday night.
As has been the case of late, very few of them came to fruition.
San Francisco stranded 12 base runners and Adam LaRoche hit a two-run home run in the sixth inning to help lift the Nationals to a 4-2 win over the Giants.
The Nationals won their fourth game in a row on a night when neither starting pitcher returned after a thunderstorm caused a 1:17 rain delay following the fourth inning.
The Giants had 10 hits and four walks against six Nationals pitchers, but went 1 for 9 with runners in scoring position.
"Same thing we've been talking about," manager Bruce Bochy said. "We get our hits. We get them out there. We just can't get them in. Again it came back to get us."
The Giants fell 14 games under .500. In their past 12 games, they're just 16 for 91 (.176) with runners in scoring position.
"Somebody's going to have to hit a gapper some time you think, and we're missing it," Bochy said.
Joaquin Arias, a last-minute replacement for Marco Scutaro (stiff back) at second base, had a career-high four hits and scored both runs, but couldn't come through with the tying run 90 feet away in the eighth inning.
After Andres Torres grounded out, moving runners to second and third with two outs and the Giants trailing by a run, Arias popped out on the first pitch he saw from reliever Tyler Clippard.
"He's facing a set-up guy with good stuff. He just popped it up," Bochy said." I have no complaints there with his game. He did all he could to help us win that game. We had some other chances."
Washington starter Gio Gonzalez threw four shutout innings before the rain came. Giants lefty Madison Bumgarner allowed just one run on an infield ground out in his four innings.
Bochy said there was no chance of Bumgarner returning after the delay.
"We talked about it the whole time and once we figured it was going to be over an hour -- I mean I don't know if an hour is the cut off -- but I guess they thought it would be better," Bumgarner said."
In the sixth, LaRoche sent a 1-0 pitch from San Francisco reliever Guillermo Moscoso (1-1) off the facing of the second deck in right field. That came after a leadoff single by Ian Desmond and broke a 1-1 tie.
Tanner Roark (2-0) earned the win with two innings of relief after the delay. Rafael Soriano got his 30th save of the season for Washington.
"Good little streak we're on," LaRoche said. "Better late than never, but we're still in a hole pretty good so we've got a lot of work to do."
The Giants had evened the score after the rain delay ended because of a Desmond error on Buster Posey's grounder with runners at first and third in the fifth.
Hunter Pence singled in Arias in the seventh for the other Giants run.
Bumgarner pitched out of trouble in the third, but Desmond began the fourth with a double to right-center field. LaRoche followed with a single to right.
Then Wilson Ramos hit a ball off Bumgarner's right knee. It deflected to third baseman Pablo Sandoval, who threw out Ramos as Desmond scored to make it 1-0.
Gonzalez remained in the game, and kept San Francisco off the board. The Giants had runners at first and second in the fourth before Gonzalez struck out Brandon Crawford looking to end the threat.
Kurt Suzuki added a run for Washington with a sacrifice fly in the eighth.
NOTES: Harper didn't start the game because he had the flu, according to Johnson, but made a pinch-hitting appearance in the eighth inning. . San Francisco CF Angel Pagan, on the DL since May 28 following surgery on his left hamstring, could start a rehab assignment at the end of this week, Bochy said. ... San Francisco starts RHP Tim Lincecum (6-11, 4.18) on Wednesday in the second of a three-game series. He faces RHP Jordan Zimmermann (13-6, 3.06).
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