HOUSTON – When John Maine struck out the side in the first inning last night, his dominance nearly took out Houston’s cleanup hitter, too.

As Maine completed the first chapter of a stellar pitching performance that his struggling club desperately needed, Astros No. 3 hitter Lance Berkman lost his bat swinging through an off-speed pitch for a third strike. Berkman’s bat went hurtling into the on-deck circle, where Carlos Lee hit the dirt in self-defense. It was an early indication of the filthy stuff Maine possessed, and the Mets right-hander struck out a career-high nine in the 6-2 victory.

Maine helped snap a four-game losing streak, getting support from Carlos Delgado’s 4-for-4 night and offensive contributions from replacements Ricky Ledee and Ramon Castro. The Mets quickly reversed the negative momentum of a three-game sweep in Colorado, in which the pitching had allowed 34 runs and 47 hits.

“We really needed it,” Delgado said of Maine’s dominance. “You need a guy who can kind of stop the bleeding, for lack of a better term.

“We didn’t play good in Colorado, so he came out today and really set the tone.”

Maine (10-4) won his fourth straight, and put thoughts of the Rockies’ sweep in the past.

“It’s unfortunate what happened in Colorado,” the right-hander said. “But you’ve gotta win one eventually – so why not tonight?”

It was more vindication for the 26-year-old, who has been snubbed twice for selection to the NL All-Star team. Last Friday night, he outdueled the Phillies’ Cole Hamels, who was named to the NL squad despite an ERA higher than Maine’s. Last night, his performance followed word that Houston’s Roy Oswalt was added to the team to replace injured Brave John Smoltz.

“I don’t even care about it any more,” said Maine, who plans to return to his native Virginia for the break. “Like I said before, I wasn’t really expecting it. . . . It would’ve been a bonus if it happened. It just didn’t work out.

“Everyone that made it was deserving, and I wish the National League the best.”

Billy Wagner, who pitched the final inning, said Maine might be the best pitcher in the NL this year. Maine allowed six hits and two runs over 72/3 innings, walking two during a career-high 121-pitch effort.

“He’s a viable candidate for Cy Young,” Wagner argued.

Delgado drove in the second Mets run and scored the third one. He has had four multi-hit games in his last eight and is hitting .419 (13-for-31) in the first eight games of the Mets’ 11-game road trip.

“This is not about me personally,” Delgado said. “It’s a good thing I’m feeling better at the plate, but I want to win as many games as I can.”

Ledee started in left because Carlos Gomez was placed on the 15-day disabled list with a fracture of the hook of the hamate bone in his left hand. Following Jose Reyes’ triple to center leading off the game, Ledee hit an RBI single that cue-balled off the first-base bag and Berkman’s left foot. With two outs, Delgado blooped an RBI single into shallow right for the second run.

“We just got lucky,” Ledee said.

Castro started because Paul Lo Duca dropped his appeal of a two-game suspension for his post-ejection antics from June 23. With two outs in the third and Maine in command, he smashed a two-run double high off the left-field fence.

Maine had seven strikeouts after three innings. He surpassed his career high of eight after the first two men reached on singles in the sixth. Maine whiffed Berkman and Lee on a combined eight pitches, never dropping below 93 mph to Lee.

“His slider was a lot better,” Castro said. “Then when he throws his fastball, they don’t have a chance.”

Mets 6 Astros 2

michael.morrissey@nypost.com