SAN DIEGO (AP) -- Kevin Kouzmanoff hit a ball as well as anyone can at Petco Park, and still lowered his head and ran hard out of the batter's box.
"In this ballpark you never know," Kouzmanoff said. "I knew it had a chance, but at the same time, the ball doesn't travel in this park. I knew I got it pretty good."
The shot came too late to give Greg Maddux the victory, but it ended a 24-hour span in which the Padres heard some pointed comments from general manager Kevin Towers and lost ace Jake Peavy to the disabled list with a swollen right elbow.
"It's nice to win. Maybe we'll do it again tomorrow," Maddux said with a wry smile.
A night earlier, after an 8-2 loss to the Cardinals, Towers said the Padres were "bad" and threatened wholesale changes if their play didn't improve. Manager Bud Black met with his players before Tuesday's game.
"Every win's nice. I don't know whether it eases anything, but I think we all know we need to play better," Black said. "We need to do more of what we did tonight, which is timely hitting. I thought we had good at-bats throughout the night. Even though we only had six hits, I saw better takes, better swings."
The win was just the fifth in 16 games for the Padres (17-30), who continue to have the worst record in the majors. St. Louis' three-game winning streak ended.
"Hey, big hit," Maddux said. "Kouz has been swinging good. He finally got ahold of one. It was nice to see."
Kouzmanoff's homer was estimated at 428 feet.
"I had a good slider," Pineiro said. "But that one, maybe I tried to make it better than what it was. It was a bad pitch and he did what he was supposed to do with it."
Manager Tony La Russa said Pineiro "made the cardinal sin by walking the leadoff hitter with a two-run lead. They walks the tying run, and throws the ball down the middle to a guy who can hit a three-run homer. You can't get away with that in the big leagues."
Pineiro had struck out Adrian Gonzalez before allowing the homer. "The way he struck out Gonzalez, he had plenty of stuff," La Russa said. "He gave them a break and they capitalized."
The 42-year-old Maddux, making his second start since earning his 350th career victory, went five innings, allowing two runs and five hits. He struck out two and walked one.
Maddux was lifted for pinch-hitter Tony Clark in the fifth, when the Padres trailed 2-0 and had a rare scoring opportunity. But with runners on second and third and two outs, Clark flied out to center field.
Bryan Corey (1-0) earned his first win with San Diego by holding St. Louis to one hit in two scoreless innings. He was acquired from Boston on May 11.
Trevor Hoffman pitched a perfect ninth for his ninth save in 11 chances. He extended his big league career record to 533. Albert Pujols, who hit two towering homers in Monday night's 8-2 Cardinals win, popped up to shortstop to start the ninth.
Pineiro (2-3) allowed three runs and six hits in 5 2/3 innings, struck out seven and walked three.
Peavy was placed on the 15-day disabled list by the Padres with a strained and swollen right elbow. The move was retroactive to Thursday, a day after he lasted just four innings against the Chicago Cubs. LH reliever Joe Thatcher was recalled from Triple-A Portland to take Peavy's roster spot. LHP Wil Ledezma will take Peavy's spot in the rotation. ... A warmup pitch by Cardinals reliever Kyle McClellan in the bottom of the seventh bounced in the dirt and hit C Yadier Molina in the mask. Molina was checked by a trainer and stayed in the game.