PITTSBURGH -- Brett Myers got credit for his sixth straight victory Friday night.
He knew who really deserved it, though.
"This one goes to the offense," Myers said. "They picked me up."
Myers (14-7) was tagged for six runs -- five earned -- and six hits. He walked four and struck out one. But thanks to Pence's hitting, he tied his career high for victories, established in 2003 with Philadelphia, and kept alive his string of pitching at least six innings in all 32 starts this season.
That is the longest streak since Curt Schilling went at least six innings in all 35 starts in 2002 for Arizona.
"I couldn't do anything," Myers said. "I didn't have command of any of my pitches, I couldn't hit the corners. Finally, I decided just to let them hit the ball."
Houston manager Brad Mills certainly wasn't complaining about his ace's outing.
"The thing is, he battled all night and he's done that all year," Mills said. "That's why he's our top-of-the-rotation starter."
The Pirates are assured of their record 18th straight losing season but this is Pittsburgh's first 100-loss year since 2001.
"It's abysmal," Pittsburgh manager John Russell said of his team's 53-100 record. "I can't sugarcoat is. It is what it is -- and it's awful."
Jeff Keppinger had three hits and two RBIs for Houston, which snapped a three-game losing streak. Angel Sanchez had two hits and two RBIs and Brett Wallace had two of the Astros' 15 hits. Just two of the Astros' hits went for extra bases, doubles by Pence and Keppinger.
"We don't have a lot of power but we do have a lot of contact hitters," Keppinger said. "We did a good job of having balls fall in."
Brandon Lyon pitched a scoreless ninth inning for his 19th save in 21 opportunities.
Pittsburgh's Garrett Jones doubled, tripled and drove in four runs and Andy LaRoche snapped an 0-for-21 skid with his first career pinch-hit home run. Andrew McCutchen also had two hits for the Pirates and Pedro Alvarez knocked in two runs.
Pence delivered the decisive hit for Houston, a two-run double off Daniel McCutchen (2-6) during a four-run sixth inning that put the Astros ahead 8-5.
With Houston trailing 5-4, Wallace led off with a single and was sacrificed to second by Myers. Jason Bourgeois then walked and Sanchez singled home Wallace with the tying run. Pence followed with his double to right-center field and scored the final run of the inning on Keppinger's single.
The Astros scored two runs off James McDonald during a 42-pitch first inning. Pence singled home the first run and Keppinger had a sacrifice fly. McDonald threw 22 pitches to the first two batters, Jason Bourgeois and Sanchez.
"Those guys at the top of the order set the tempo for the whole game," Pence said. "It's the equivalent of making the pitcher run 22 sprints in a row, considering the energy and effort it takes for each pitch."
McDonald lasted four innings, allowing three runs and five hits with two walks and four strikeouts.
Jones had his first RBI with a ground out in the bottom of the first and his two-run double tied it 3-all in the third after Sanchez hit a run-scoring single in the second.
Chris Johnson singled in a run for Houston in the top of the fifth but the Pittsburgh regained a short-lived 5-4 lead in the bottom of the inning as Jones hit a sacrifice fly and Alvarez followed with a run-scoring double.
LaRoche's home run, which hit the top of the left-field fence and bounced into the stands, came in the bottom of the sixth and cut Houston's lead to 8-6. The Pirates made it a one-run game in the seventh as Jones tripled and scored on Alvarez's sacrifice fly but Humberto Quintero and Geoff Blum hit RBI singles in the ninth to make it 10-7.
Pittsburgh LF Jose Tabata left after the third inning with a sore left knee after beating out an infield single that extended his hitting streak to eight games Houston CF Michael Bourn missed his fifth straight game with a strained right oblique muscle and acknowledged that there is a strong possibility he could miss the remainder of the season The loss dropped the Pirates to 38-41 at PNC Park, costing them a chance to join the 2006 Tampa Bay Devil Rays as the only team to lose 100 games and have a winning home record in the same season.