HOUSTON (Ticker) -- Scott Elarton tossed 7 1/3 strong innings for his fourth straight victory and was backed by three home runs as the Houston Astros posted a 9-5 victory over the Kansas City Royals.

Elarton (8-3) allowed five runs -- one earned -- and four hits while tying a season high with eight strikeouts. He improved to 5-0 at hitter-friendly Enron Field and has produced the last four wins the Astros have had over the past 15 games.

"I can't say a specific reason but I think when he goes to the mound he expects to win," Houston manager Larry Dierker said of Elarton's success at home. "I think some of our guys who have had problems here go to the mound hoping to win. He has an aura about him. He's not afraid to go after the hitter and throw strikes."

Kansas City did not get its first hit until Jorge Fabregas' home run in the fifth inning and did not have another baserunner reach second until the eighth.

"Early, I didn't feel right," Elarton said. "I wasn't hitting my spots. I was lucky they fouled some bad pitches off. I thought I got my rhythm about the fifth inning and I felt good after that. I feel more comfortable and I have tons more confidence."

Elarton has allowed just five earned runs in his last 29 innings and the Astros are averaging 8.1 runs a game when he takes the mound.

"I used to be afraid to let them hit the ball and know I want the hitters to hit the ball," Elarton said. "I'm being more aggressive with my pitches. I'm also getting more run support. I wish I could bottle it up. It's a lot easier to pitch with a lead."

Marc Valdes relieved Elarton with one out in the eighth inning and allowed a sacrifice fly by Jermaine Dye and rookie Mark Quinn's two-run single that cut the lead to 9-5. Valdes rebounded to strike out Joe Randa to end the threat before tossing a scoreless ninth.

Houston committed three errors in the inning, including two by rookie shortstop Julio Lugo.

"It was a great win all the way around," Dierker said. "We got a little sloppy in the end, though we had a cushion to keep the lead. Elarton did a great job. He pitched well, he played good defense, and he even got a couple of hits."

In the third inning, Elarton singled and scored on Lugo's double before Biggio belted a full-count pitch from Royals starter Blake Stein (0-1) over the left-field fence for his fifth homer. Biggio, who has just two homers at Enron Field, overcame a high ankle sprain suffered in Thursday's game and also tied a team season-high with three runs scored.

"I've been working on some things and in the last two-and-a-half weeks it's felt better. The biggest thing for me is to feel comfortable in the box. I think this is a start."

The Astros opened a 6-1 lead in the bottom of the fifth on Jeff Bagwell's three-run blast before rookie Mitch Meluskey hit his ninth homer leading off the sixth for a six-run bluge. Bagwell has five home runs in the last six games.

Stein, making his season debut after being sidelined with a cracked bone in his right forearm, allowed six runs and seven hits in five innings.

Kansas City has dropped 17 of 23 to fall a season-low seven games under .500.

"He pretty much shut us down the first seven innings," Royals first baseman Mike Sweeney said. "We couldn't do much against him. He mixed up his pitches real well. He has four pitches and he threw them all for strikes."

The win snapped Houston's season-high six-game home losing streak, which was the longest since a seven-game slide at the Astrodome from June 6-22, 1995.