"With one swing, Ryan Ludwick proved what he could mean in a pennant drive.

The former Cardinal launched a three-run homer Saturday, snapping a 4-4 tie with one out in the top of the ninth, to lead the Padres to an 8-4 victory in yet another of what seems to be an endless stream of make-or-break victories.

The win ended a run of 11 straight Padres losses in St. Louis dating back to 2007.

More importantly, it boosted the Padres' hopes in both the National League West and wild card races with 14 games to go.

The win, coupled with the Giants' 2-1 loss to Milwaukee later Saturday, gave the Padres a half-game lead in the division.

"That's the biggest," Bud Black said of Ludwick's 353-foot drive into the left field seats.

But the Padres manager could just as easily have been speaking about the importance of the win - only the Padres' seventh in the last 23 games and one that snapped a three-game losing streak.

Ludwick capped a day that began on an emotional high with Chris Young making his first start since the season's second game. The 6-foot-10 right-hander held the Cardinals to one run - which scored on a wild pitch - on three hits and three walks over four innings.

"Seeing Chris back out there today and competing like he competes gave this ballclub a lift," said David Eckstein. "And to finish it like that …"

For Ludwick, it was a double bonus.

"I know it was a huge hit," Ludwick said. "And it's an added bonus to do it to your former club in their park."

Down 1-0 and 2-1 early, the Padres took a 4-2 lead in the seventh, with RBI singles by Will Venable, Miguel Tejada and Adrian Gonzalez capping the six-hit inning. But the Cardinals tied the game in the bottom of the inning and it was still deadlocked as the Padres opened the ninth.

Eckstein, another former Cardinal, led off the inning with a single to left. Running on a full-count pitch, he reached second on Miguel Tejada's hopper back to the mound.

St. Louis reliever Kyle McClellan then intentionally walked Gonzalez to pitch to Ludwick, who came to the Padres from St. Louis in a three-way July 31 trade that also involved the Cleveland Indians."