CINCINNATI -- Houston native Paul Janish gave his family and friends something to cheer about -- even if he did help beat the Astros.
"I was kidding around with some of their guys before the game about it being televised in Houston," said Janish, who was born and still lives in Houston and went to Rice University. "I said, 'I've got to do something.' It's good playing in front of the home fans."
Houston reliever Sammy Gervachio (1-1) opened the seventh by hitting Corky Miller. Pitcher Bronson Arroyo ran for Miller and was sacrificed to second by pinch-hitter Drew Sutton.
Drew Stubbs struck out, but Janish lined up an opposite-field double to right-center to help send the Astros to their third consecutive loss.
Janish improved to 6 for 13 spanning his past three games after a 2-for-32 slump, prompting manager Dusty Baker to give him a rest last Saturday in Chicago.
"I think the day off helped him gather his thoughts," Baker said.
Janish, given first crack at the shortstop job after Alex Gonzalez was traded to Boston on Aug. 14, jokingly credited the presence of his mother, Debbie.
"She usually brings some hits with her," he said. "[The slump] was on my mind, but it's not something you worry about. I was kind of in a funk, and it helped mentally. I just want to keep playing every day and finish strong."
Daniel Ray Herrera (4-4) struck out Michael Bourn, the only batter he faced, to end the seventh and earn the win.
Nick Masset allowed a hit and struck out the side in the eighth, and Francisco Cordero pitched the ninth for his 36th save.
The Reds have won three of four.
Houston starter Roy Oswalt, roughed up for six runs and 10 hits in two innings while dealing with a bad back in his previous start on Sept. 10, pitched into the sixth. He allowed six hits and four runs with no walks and three strikeouts.
Kip Wells rebounded from a 28-pitch first inning and lasted 6 2/3, giving up five hits and four runs with two walks and one strikeout. He retired 13 consecutive batters before Jeff Keppinger's one-out single in the seventh.
"We started out well against Wells, but we didn't do a whole lot after the first inning," Houston manager Cecil Cooper said. "He started to go with his off-speed stuff. Sometimes, guys figure it out."
Wells got himself immediately into trouble by walking Bourn on four pitches to lead off the game. Bourn, who entered leading the National League with 55 stolen bases, swiped second and scored on Kaz Matsui's lined single to center field.
Matsui stole second, moved to third on a groundout and scored on a single by Miguel Tejada, who stole second and scored on Geoff Blum's single, a sharp grounder that just eluded the diving backhand stab of second baseman Brandon Phillips.
"They were running crazy," Baker said. "Every stolen base ended up scoring. Kip was a little shaky, but he settled down big time. He found his command."
Stubbs led off the bottom of the first by hitting the first pitch he had ever seen from Oswalt into the lower deck in left field for the rookie's sixth home run since being called up on Aug 19. Two pitches later, Janish doubled to deep right-center and later scored on Scott Rolen's sacrifice fly.
Matsui led off the third inning with his sixth home run of the season and first in 139 at-bats since Aug. 3 against San Francisco.
The Reds tied it in the sixth. Janish and Joey Votto led off with doubles, though Janish could only get to third after waiting to see if left fielder Carlos Lee would make a sliding catch of Votto's blooper -- he didn't. Doug Brocail relieved Oswalt. Phillips grounded to second to drive in Janish, and Rolen hit a fly ball to deep center field over the head of the drawn-in Bourn for a ground-rule, tying double.
"The last curveball in the fifth, my back tightened a little," Oswalt said. "I tried to get through the heart of the order in the sixth, but I didn't have enough. I'll see how it feels tomorrow."
Janish became the first Reds batter with three doubles in one game since Jorge Cantu on Sept. 21, 2007, at San Francisco ... Houston 1B Lance Berkman was scratched from the Astros original starting lineup when pregame treatment didn't clear up back and hip problems. Manager Cecil Cooper said Berkman might be sidelined until Friday. ... Matsui, originally scheduled to get the night off, was in Houston's second lineup. ... Astros' RHP Jose Valverde remained in Houston with a high fever and sore throat. ... OF Laynce Nix was activated by the Reds and started in left field ... ESPN college basketball announcer Dick Vitale watched the game with Reds owner Bob Castellini.