Houston ? The way the Kansas City Royals’ season has gone, Doug Mientkiewicz doubted his fly ball in the ninth inning actually would be a home run.

For a change, the Royals got the luck they needed.

Mientkiewicz’s three-run shot lifted the Royals to a 7-4 victory over the Houston Astros on Sunday.

“I didn’t think it was going out,” said Mientkiewicz, who homered for just the second time this season. “That’s the way the season has gone. When it headed out there, I just thought, ‘Here we go again.”‘

Instead, the Royals took two out of three from the Astros, finishing a seven-game road trip with an encouraging 3-4 mark.

“We’ve played really well on this trip,” Royals manager Buddy Bell said. “That’s the important thing.”

Kansas City right fielder Reggie Sanders, right, makes the catch over second baseman Mark Grudzielanek on a popup by Houston's Morgan Ensberg. The Royals beat the Astros, 7-4, on Sunday in Houston.

John Buck and Reggie Sanders also homered for Kansas City, which snapped a three-game home-run drought. The Royals also extended their error-less streak to eight games, a season high.

The Royals blew a 4-1 lead, but rallied off Houston reliever Chad Qualls (3-2) to win for the third time in nine games.

“This should give us some momentum,” Buck said, “and any momentum we can get, we’ve got to take it and run with it.”

Preston Wilson homered, and Chris Burke had three doubles for the Astros, who lost for the third time in 12 games.

After winning their first seven series at Minute Maid Park, the Astros have dropped three of their last six.

“This was not what we expected this weekend,” Burke said.

Kansas City salvaged a solid start from Brandon Duckworth, who was acquired from Pittsburgh on June 10. Duckworth scattered six hits and allowed two runs in his second start with Kansas City. He had a similar line Wednesday in Anaheim, but the Royals lost, 4-1.

“He’s got real ability,” Bell said. “He’s able to muscle up, at times, and get a little more on his fastball. Our pitching has been pretty good on this whole road trip.”

Emil Brown started the one-out rally off Qualls with a double over Burke’s head in center field. Matt Stairs drew a walk, bringing up Mientkiewicz, who had one extra-base hit in his last 14 games.

Mientkiewicz battled Qualls to a 3-2 count, then pounded a fastball into the right-field seats, just over the head of backup right fielder Orlando Palmeiro.