ST. LOUIS -- The sudden chill that swept over downtown St. Louis gave Saturday's matinee an October vibe. It also reminded Tyler O'Neill of home. Which is why the Canada native, already soaked after his walk-off home run sent the Cardinals to a 5-4, 10-inning win over the Giants, asked

ST. LOUIS -- The sudden chill that swept over downtown St. Louis gave Saturday's matinee an October vibe. It also reminded Tyler O'Neill of home. Which is why the Canada native, already soaked after his walk-off home run sent the Cardinals to a 5-4, 10-inning win over the Giants, asked for more than the traditional water-cooler shower.

"I made sure they drenched some ice on me," O'Neill said. "I like the cold weather."

Bare-chested on the Busch Stadium grass, O'Neill struck a heroic pose. His theatrics capped a game his manager called a "vintage" day, salvaging what might have been Adam Wainwright 's final start in St. Louis. And it got even better at night, after the Brewers lost to the Pirates, moving the Cardinals within two games of Milwaukee for the top National League Wild Card spot. They also remained 1 1/2 games up on the Rockies for the second Wild Card, after Colorado won a late game in Arizona. St. Louis has now won five of its last six games, and will go for a sweep Sunday ahead of two all-important series with the Brewers and Cubs.

"I've had some walk-offs in the Minors," O'Neill said. "But nothing compares to being in a pennant race."

On the opposite side of the Cardinals clubhouse, Wainwright grinned. He's one of the few in St. Louis' youth-infused locker room who's been here before. And now, after spending much of the season injured and inactive, he's re-emerged as a big reason, with seven games to play, the Cards once again have October squarely in their sights.

"To be in the moment here in September is really special," Wainwright said. "I'm glad some of our young guys are playing meaningful games. We haven't played in the postseason in a few years, it's about time we do that again."

Wainwright is so focused on the team's postseason fortunes that the idea of Saturday marking the 37-year-old's final start in St. Louis "barely weighed on me at all," he said. It remains a very real possibility, with his next start set for the season's final weekend in Chicago and Wainwright's contract up at the end of the year. But after Wainwright spent six more innings largely silencing an opponent -- he ended up allowing four earned runs after a barrage of bad luck soured his line -- those unknowns drifted even further from the periphery.

"I don't think Waino or this team feels like that might have been his last start at Busch," manager Mike Shildt said. 'I'd love to see him in the playoffs, pitching at Busch."

And perhaps he will. That's certainly more likely now, after Wainwright, Yadier Molina and O'Neill dragged the Cardinals past a season-high four errors, and Carlos Martinez set the stage for their 11th walk-off win. Wainwright was dominant until two errors and three bloop singles gave the Giants a lead in the seventh, one Molina immediately nullified with a game-tying, two-run homer off Dereck Rodriguez in the bottom of the frame.

"Vintage is a good word for that," Shildt said of Molina and Wainwright, the longest-tenured teammates in Major League Baseball.

After Dakota Hudson (1 2/3 scoreless) pushed the Cardinals past regulation, two more miscues -- on one misplay by Matt Carpenter -- put Martinez in a bases-loaded jam in the 10th. But Martinez, pitching for the fourth time in six games, struck out Alen Hanson and Austin Slater to end the threat. That set up O'Neill, who sent a 2-2 curveball from Mark Melancon 410 feet over the left-field wall. The blast lifted St. Louis to its 11th walk-off win of the year and ignited the paid crowd of 45,878 at Busch.

"It's definitely leading up to a postseason atmosphere," O'Neill said. "Finishing it off for the guys was a great feeling."

SOUND SMART

• Molina's home run was the 145th of his career, passing his brother, Bengie, for the most in the Molina family.

• Of the eight hits Wainwright allowed, none of them exceeded the 95 mph exit velocity threshold Statcast™ deems "hard-hit." Said Wainwright, who has struck out 18 in 17 1/3 innings since returning from the DL: "That's probably the softest four runs I've ever given up. That was incredible."

YOU GOTTA SEE THIS

Martinez would not have wiggled out of the ninth without help from Yairo Munoz , who, in place of injured Kolten Wong , made a Wong-like play at second base to take a hit away from Gregor Blanco . Munoz charged Blanco's soft grounder and threw from the ground to record the second out of the inning.

HE SAID IT

"I don't want to get into that. That's an HR [Human Resources] issue." -- Shildt, on O'Neill's teammates ripping his shirt off postgame

UP NEXT

Miles Mikolas (16-4, 3.01 ERA) has a chance to pitch himself into a tie for the National League lead in wins with a victory Sunday, when the right-hander takes the ball for the finale of St. Louis' three-game set with San Francisco. Doing so would only add to the list of accomplishments for Mikolas, who also leads the league in walk-rate in his first season back from Japan. Lefty Andrew Suarez (7-11, 4.24) opposes for the Giants, with first pitch slated for 1:15 p.m. CT from Busch Stadium.