SAN FRANCISCO (AP) - Jordan Schafer homered and scored three times, Henry Sosa pitched six strong innings against his former club to earn his first career victory and the Houston Astros beat the San Francisco Giants 3-1 on Thursday night to end a four-game losing streak.
J.D. Martinez doubled twice and had two RBIs for the Astros, who stole a season-high four bases and turned three double plays on defense. Houston, which still owns the worst record in the majors at 43-88, has won three of four against the defending World Series champs.
Orlando Cabrera drove in San Francisco's only run with an RBI groundout in the third. The Giants, losers of five of seven, fell three games behind first-place Arizona in the NL West.
Sosa (1-2) pitched with runners on base every inning but limited the damage with a crisp fastball and slider that baffled the Giants most of the night.
The rookie right-hander, who began the season with the Giants before being shipped to Houston as part of the July 19 trade that sent infielder Jeff Keppinger to San Francisco, allowed only four singles and struck out three in his second straight start against his former team.
Sosa got just enough support from his teammates.
Schafer singled and scored in the first, walked and scored in the third and then homered off Giants starter Ryan Vogelsong in the seventh. It was Schafer's second home run for the Astros and the fourth of his career. He had gone 148 at-bats since his last home run on June 13, with Atlanta.
Wilton Lopez pitched two scoreless innings and Mark Melancon worked the ninth for his 14th save in 18 chances.
San Francisco had the potential tying run at the plate in the ninth after Carlos Beltran's leadoff single but Pablo Sandoval hit into a 3-6-3 double play before Aubrey Huff flied out to end it.
Vogelsong (10-4) gave up six hits over 7 1-3 innings but lost for the third time in four starts.
Since beginning the season 8-1, Vogelsong is 1-3 with a 4.00 ERA over his last four starts. The Giants have scored only one run in the three losses.
It was just the latest setback for San Francisco's pitching staff, which has been beset by a rash of injuries lately.
The Giants, who have lost the opening game in their last 11 series, have even bigger issues with their offense. They put the leadoff hitter on base in five consecutive innings but hit into three double plays and had two runners caught stealing.
Martinez doubled in Schafer in the first, then added a sacrifice fly in the third to score Schafer again, making it 2-0.
Houston's rookie left fielder, who began the season with Double-A Corpus Christi, has nine RBIs over his last five games. Martinez also has eight RBIs in four games against San Francisco this season.
The Giants, held to two runs or fewer in four of their previous eight games, cut the gap to 2-1 on Cabrera's RBI groundout in the third. They got some help from Sosa, called for a balk after Eli Whiteside singled and was sacrificed to second.
Sosa's best work came in his final inning.
Cabrera walked to start the sixth and was sacrificed to second, putting the potential tying run on base. Sosa, who had a no-decision against the Giants last Sunday, retired Beltran on a comebacker and then got Sandoval to ground out to third.
Schafer made it 3-1 with his two-out homer in the seventh.
NOTES: San Francisco's last win in a series opener was on July 18 against the Dodgers. ... Giants closer Brian Wilson played catch briefly before the game but manager Bruce Bochy is unsure if the All-Star closer will be ready to come off the disabled list when he's eligible next week. "I wouldn't rule it out, but it's going to be tough for him to be ready to go when his time is up," Bochy said. ... LHP Barry Zito (mid-foot sprain) may throw off the mound in Arizona as early as Friday. ... Whiteside was activated from the disabled list. Backup catcher Hector Sanchez was optioned Class-A San Jose to make room. ... The Astros called up LHP J.A. Happ from Triple-A Oklahoma City to start Friday. Happ (4-14) had a 1.50 ERA in three starts in the minors. ... The Astros optioned OF J.B. Shuck down to make room for Happ. ... LHP Madison Bumgarner (7-12), who has a 3.51 ERA over four starts in August, goes for the Giants.
