Houston ? Kansas City right-hander Denny Bautista showed again Sunday that he might already be over those rookie nerves.

Bautista pitched 5 2/3 scoreless innings, and Alberto Castillo hit a two-run homer, leading the Royals to a 9-6 victory over Houston in the final exhibition game for both teams.

Inserted into the Royals’ rotation despite a disappointing audition at the end of last season, Bautista closed out his impressive spring with a dominant effort against the Astros. He gave up only three hits, struck out five and walked two, showing poise that he clearly lacked after being called up from the minors in 2004.

“It’s very simple … he’s more calm,” Royals manager Tony Pena said. “He doesn’t let anything bother him now. He can make a mistake and get by with it because of his stuff. Time will tell, but he can be real good.”

The 24-year-old Bautista is yet another one of the intriguing prospects the Royals will count on this season, and like most of them, he’s optimistic things can be different for the longtime AL Central doormat in 2005.

Bautista spent all winter and spring tinkering with his awkward mechanics, and the changes seem to have paid off: He finished spring training 2-0 with a 2.84 earned-run average.

“I did a lot of things differently,” said Bautista, who went 0-4 with a 6.51 ERA in five starts in the final month of last season. “This year, I’ve got command of my fastball.”

Meanwhile, the Royals — of all teams — made sure the Astros’ search for a fifth starter will last into the regular season.

A day after essentially being promoted into the rotation, Brandon Duckworth followed with a woeful four-inning start.

Duckworth allowed eight runs on 10 hits, including homers by Castillo and Angel Berroa. He was finally chased in the fifth after giving up a walk and two singles, drawing a smattering of sarcastic applause when he trotted back to the dugout.

“If you’re going to let one game bother you, you shouldn’t be here,” Duckworth said. “I’m just going to keep throwing and doing what I was doing before today … doing what I’ve been doing all spring.”

Saturday, Duckworth got the initial nod over top prospect Ezequiel Astacio in the competition to be the fifth pitcher when Astacio was optioned to Triple-A Round Rock.

The 29-year-old right-hander, who split 2004 between Houston and then-Triple-A New Orleans, outlasted seven other pitchers during spring training with six solid appearances, including three starts.

And though Duckworth looked shaky in a six-inning outing against Cleveland last week, Houston was comfortable enough to pick him over Astacio, who had a team-best ERA of 1.35 in five spring appearances.

That move might only be temporary after Duckworth’s struggles Sunday.

“Brandon has obviously got to stop the big innings, and he’s got to make better pitches,” Astros manager Phil Garner said. “Today he got some up and over the plate, and they hammered him.”