ST. LOUIS -- Every fifth day, the Cardinals are world-beaters. Fortunately, that's often enough in the National League Central.

Ace Chris Carpenter improved to 14-6 with another brilliant game as St. Louis thumped Houston, 7-0, in the opener of a three-game series at Busch Stadium on Monday night. The Cardinals are 19-10 when Carpenter takes the mound and an even 57-57 with any other starting pitcher.

Ronnie Belliard snapped an 0-for-20 slump emphatically, rapping an RBI single and a three-run triple for the bulk of the Cards' offense. St. Louis scored five runs on just two hits in the fourth inning.

All Carpenter needed, however, was Juan Encarnacion's tie-breaking RBI single in the third and some defense behind him. The reigning NL Cy Young Award winner bolstered his case for a second straight trophy with his third shutout and fourth complete game of the year. All other Cardinals starters have combined for one complete game and no shutouts.

"Tonight was a nice night against a quality offensive team that plays us tough," said Carpenter. "It was a big win."

Albert Pujols is pushing for a second straight NL MVP Award, but the case can be made that no one is more valuable to the Cardinals than their No. 1 starter.

"Everything hasn't worked for him this year," said manager Tony La Russa. "Sometimes, we don't score. And he has just ignored everything and gotten ready to pitch, and he's putting together another great season."

The win expanded St. Louis' lead to five games over second-place Cincinnati in the NL Central and six games over third-place Houston. Each of the three teams has 19 games remaining in the season, so the Cardinals' magic number is 15 to eliminate the Reds and 14 over the Astros.

A large amount of that lead is attributable directly to Carpenter, who is 50-16 in a St. Louis uniform. The Cardinals have won 64 of his 89 starts over three seasons, a remarkable .719 winning percentage.

"He can throw anything for a strike," said Houston shortstop Adam Everett, who singled in three at-bats. "And he can throw it to both sides of the plate. When you can do that, throwing 94, 95 [mph], taking some off of his cutter, anywhere from 85 to 90 [mph] -- and he's got that big curveball -- it's why he won the Cy Young last year and may win it again this year."

Carpenter has made 12 starts since the All-Star break. In eight of those games, he's gone at least seven innings and allowed no more than two runs. After a late-season fade in 2005, it appears that he'll have nothing of the kind in '06.

"I learned from last year," he said. "That was something I learned, that no matter what the situation was, not to give them away. I don't plan on giving them away. I'm trying as hard as I can to stay locked in and stay focused on what I need to do. I don't buy into what the situation is in the standings."

With his third shutout, Carpenter moved into a tie with Brandon Webb for the NL lead in that category. Already the league's ERA leader, Carpenter moved to within one victory of Brad Penny for tops in the NL. No other Cardinals starter has pitched a shutout this year, and no other pitcher has won a complete game for St. Louis -- Anthony Reyes' one-hit loss in Chicago is the only other CG by a Cards hurler.

The Cardinals are no better than three games over .500 with any other pitcher on the mound -- they went 10-7 in Mark Mulder's 17 starts before Mulder was shelved for the year with shoulder trouble. Among active starters, the team's next best record is 15-13 behind Jeff Suppan.

It helped Carpenter that an offense that struggled mightily on a 2-5 road trip came to life on Monday. After stranding leadoff baserunners in the first and second innings, the Cardinals broke through in the third against Taylor Buchholz, who fell to 6-10 in a spot start for Andy Pettitte. Encarnacion bounced a two-out single up the middle to score Chris Duncan for the game's first run, and Belliard added an RBI single to make it 2-0. Belliard's hit snapped an 0-for-20 slide.

Belliard made it a much bigger night in the next inning. His three-run triple capped a five-run outburst that put Carpenter and the Cards in complete control. The only other base hit in the inning was Duncan's one-out double. St. Louis also scored on a Scott Rolen bases-loaded groundout and a walk to Encarnacion, also with the sacks full.

"I was just seeing the ball and hitting it," Belliard said. "[The triple] got up in the gap. I never thought the ball was going to jump like that."