The Houston Astros powered their way to a season-best sixth straight win.Lance Berkman hit a tie breaking home run in the fifth inning and Jeff Kent capped a five-run seventh with a grand slam as the Astros beat the Cincinnati Reds 9-3 yesterday.In sweeping the three-game series against the Reds, the Astros hit 10 home runs and scored 28 runs.”We got some big hits, some big blows,” manager Phil Garner said. “We got three runs the old-fashioned way, then ‘Boom.’ We got five runs just when we were trying to put another run on the board.”Houston has won 14 of its last 17 games.”They’re hot,” Reds manager Dave Miley said. “Phil probably wants to play tomorrow.”Roy Oswalt (16-9) improved to 10-0 in 14 career games against Cincinnati. He left after six innings with sore ribs, allowing three runs and six hits, walking three and striking out four.”I can’t explain it,” he said of his success against the Reds. “Through the years, they’ve changed players, and they have good players. We just seem to match up well, and it always seems like we score a lot of runs here.”Paul Wilson (9-5), who came off the disabled list earlier in the day, failed in his eighth attempt to earn his 10th win. He allowed four runs and six hits in five innings.”Physically, I felt fine,” said Wilson, who hasn’t won since beating Milwaukee in the last series before the All-Star break. “I felt great. Maybe a little herky-jerky and a little out of control at times, but physically, it was a positive — the only positive.”I was frustrated. I was hoping for a little better outing.”With two out in the fifth, Berkman hit his fourth homer of the series and 25th of the season to break a 3-all tie.Houston put the game away with a five-run seventh that included Kent’s 11th career grand slam — and 20th homer of the season.”It was a fastball,” Wagner said of the 2-0 pitch. “I got it up a little bit. I fell behind in the count a little bit, and a guy like that is not going to miss a mistake.”The Reds fell to a season-worst eight games under .500.Cincinnati opened the scoring when Ryan Freel singled to center and moved to second as Carlos Beltran bobbled the ball for an error. Juan Castro sacrificed Freel to third, and Sean Casey drove him in with a sacrifice fly.Houston took a 3-1 lead in the second on sacrifice flies by Eric Bruntlett and Craig Biggio, and an RBI single by Oswalt. The Reds tied it in the third on Freel’s leadoff home run and Darren Bragg’s two-out, broken-bat RBI single to right.Notes: The Reds activated INF Brandon Larson from the disabled list. Larson had been sidelined since July 19 with a strained left hamstring. … Freel’s homer was his first in 373 games.