MILWAUKEE -- The Brewers had finally gotten to Adam Wainwright in the ninth when St. Louis manager Mike Matheny came to the mound to check if his ace right-hander was tiring.
Matheny didn't expect an honest answer. Wainwright stayed in the game anyway.
Wainwright got Gerardo Parra to bounce into a double play for his fourth complete game of the season, and the Cardinals beat sliding Milwaukee 9-1 on Sunday.
"I told him he had a short leash. I'm still waiting for that day when I go out there and he's actually honest if he doesn't feel good," Matheny said.
The Cardinals won three of four at Miller Park and lead the NL Central by 4½ games over Pittsburgh, which beat Chicago 10-4 at Wrigley Field on Sunday.
"Now's the time we've got to keep the throttle down," Matheny said. "This game can reach up and grab you."
The Brewers are well aware of how quickly fortunes can change. Losers of 11 of 12, their freefall continued after spending nearly five months atop the NL Central before dropping into second on Sept. 1.
They fell into third after Sunday's loss, leapfrogged by Pittsburgh. The Pirates also moved a half-game ahead of Milwaukee for the second NL wild card.
"There's no excuse ... it's tough," outfielder Carlos Gomez said. "We know we're not playing like a team. Just put it in the past and come tomorrow and win the ... game."
It was more than enough support for Wainwright (17-9), who is tied for the major league lead in victories. The right-hander allowed seven hits in his 20th career complete game.
Wainwright had allowed at least three runs in each of his previous three starts, failing to get out of the sixth each time.
But feast-or-famine Milwaukee managed just an RBI single by Gomez.
"Today was obviously a big win for our team, but you know just a realization of all the little steps I've been taking over the last few weeks -- I knew it was a matter of time," Wainwright said.
And on cue, the Cardinals are in the middle of another September surge.
They held the Brewers scoreless until Gomez's pinch-hit single in the ninth drove home Scooter Gennett from second. It was Gomez's first at-bat in a week after being sidelined with a left wrist injury.
The Brewers helped out Wainwright by grounding into three double plays and committing three errors.
"We do this once in a while, and I sure don't like to see it. They don't like it. They work hard, they give a good effort and then we play this sloppy," manager Ron Roenicke said.
Milwaukee's first miscue came at the start of St. Louis' four-run fourth, when Nelson's pickoff attempt of Jon Jay squirted past Jonathan Lucroy at first. Jay then scored on Matt Adams' sacrifice fly.
Later, Bourjos' liner landed in the gap in left-center and bounced to the wall. The speedy outfielder had more than enough time to sail into third after driving home two runs for a 4-0 lead.
"I don't think we've always been clicking on the right cylinders," Bourjos said. "Everybody's clicking right now."
Cardinals SS Jhonny Peralta got the 1,500th career hit with a fourth-inning single. He added his 20th homer of the year with a two-run shot in the ninth.
Cardinals: LF Matt Holliday got a day off. Holliday has gone hitless in four of his last five games, with the exception being a three-hit outing on Thursday night in Milwaukee.
Brewers: Gomez had been used as a pinch runner and defensive replacement in recent days before his pinch-hitting appearance Sunday. Roenicke said Gomez was due to see the team doctor Sunday to determine if his star outfielder was ready to return to the starting lineup Monday.
Cardinals: Shelby Miller (8-9) gets the ball for the start of a four-game series Monday against Cincinnati. Matheny said he expected another wave of minor-league reinforcements to join the team then.
Brewers: Yovani Gallardo (8-8) opens a four-game series at home against Miami. He is 5-0 against the Marlins in seven career starts.