SAN DIEGO -- Mark Mulder recorded fewer outs and allowed more baserunners than his opposite number, Woody Williams, on Tuesday night. He was less efficient than Williams, whom he replaced in the Cardinals' rotation this past offseason.

He was also the winning pitcher as the Cardinals beat the Padres, 4-2, while Williams (5-7) took the loss in his first game against his former team. The Cardinals won their fifth straight series opener. San Diego, meanwhile, is stuck in an eight-game losing streak.

The difference in Tuesday's game, a matchup of division leaders, was not so much the starting pitchers as the men behind them. Mulder (12-5) and a string of St. Louis relievers were continually bolstered by the Cardinals' defense, in the form of three double plays, an outfield assist and a couple of other gems.

Injuries have wracked the Cardinals' offense, but defensively the National League's top team remains strong.

"No matter where you go, if you pitch and defend, you're going to be in the ballgame and have a chance," said manager Tony La Russa. "And we've been pitching and defending."

Mulder allowed nine base hits, walked three against one strikeout and needed 110 pitches to get 17 outs. But the southpaw survived to get the victory, though not without the aid of a slew of fielding gems. So Taguchi threw out Eric Young at second base on what should have been a Mark Loretta single in the first. Jim Edmonds tracked down several balls deep in center.

And then there was Mark Grudzielanek, hanging in and making the pivot on one tough double play after another. He turned all three, and none of them were easy.

"People think that's routine stuff going on out there," Grudzielanek said. "Some of it is, but there's a lot of it that's not routine."

His teammates know.

"Grud put on a clinic out there, turning double plays," said shortstop David Eckstein. "Those guys are all over him, and he found ways to do it. ... He's going to throw it. He's got one of the quickest releases you're ever going to see. He gets it, and then it's gone. That's pretty nice."

Grudzielanek leads Major League second basemen in double plays and assists, both by wide margins. St. Louis has turned the most twin killings in the Majors as a team. That's partly due to a staff that gets groundballs, but the infielders still have to take advantage.

"He does a great job of turning the double play," said closer Jason Isringhausen. "We all know that. He's got a great arm."

On the offensive side, the Cardinals scored in just the way they'll have to do for a while: with a big dose of Albert Pujols and pitch-in contributions from all over the lineup. Pujols doubled and homered in the win, giving him nine extra-base hits in 11 games since the All-Star break. With Scott Rolen, Reggie Sanders and Larry Walker all on the disabled list, Pujols' production becomes more vital than usual.

Meanwhile, three of the fill-ins trying to help keep the NL Central leaders afloat chipped in to support Pujols. Taking Sanders' spot in left field, John Gall singled, doubled and scored twice in his big-league debut before being removed in a double switch.

"You try to not look left or right, just look at the pitcher," said Gall. "There's nerves, there's jitters. Natural reaction."

Taguchi, playing right field for Walker, reached base three times and drove in a run. Einar Diaz, catching in place of the injured Yadier Molina, brought home the Cardinals' first run when he hit into a second-inning double play. Diaz picked up an RBI with a squeeze bunt that capped off the sixth.

A Cardinals bullpen that has been stung a few times in recent days regained form on Tuesday, though it wasn't always seamless. Cal Eldred came on for Mulder to close out the sixth, and Randy Flores and Julian Tavarez picked up for Eldred after he walked the leadoff man in the eighth. Tavarez issued a walk and a base hit but got a double play in the eighth before handing over to Ray King. And Isringhausen picked up his 28th save in 31 chances.

It was Isringhausen's 129th save as a Cardinal, tying him with Todd Worrell for second on the team's all-time list.