Francisco Cordero rarely gives up homers -- especially with his Brewers one out from a win. Rickie Weeks rarely bobbles easy grounders.
The extra-inning slips set up Mark Teixeira's winning single in the 11th Saturday, giving the Atlanta Braves a 4-3 victory and leaving Milwaukee facing a 2 1/2-game deficit in the NL Central.
The division-leading Chicago Cubs beat Pittsburgh 9-5 earlier in the day.
"We're down 2 1/2 with eight left. That's not good math," said Milwaukee's Corey Hart, whose 10th-inning homer gave Milwaukee a 3-2 lead.
Brewers manager Ned Yost refused to take a dim view of his team's chances.
"We're 2 1/2 good days from being back in first place, and as far as I know we have a week left, so no, just play it day by day," Yost said.
Needing to win, the Brewers were one out away in the 10th when Cordero gave up a tying home run to pinch-hitter Scott Thorman.
Edgar Renteria drew a leadoff walk from Seth McClung (0-1) in the Braves 11th and Willie Harris pinch-ran. Brian Shouse relieved, and Chipper Jones hit an easy grounder that Weeks misplayed.
"I just missed the ball," Weeks said. "I was trying to get the ball to the shortstop for two."
Teixeira, watching from the on-deck circle, said he knew that Weeks' 13th error gave the Braves an opening.
"I knew it was over," Teixeira said. "Whether I was going to do it or I was going to get the runner over and let Mac (Brian McCann) or Frenchy (Jeff Francoeur) do it, I knew we were going to win that game."
Teixeira singled past first baseman Prince Fielder to win it.
Of the Brewers' remaining eight games, the final seven are in Milwaukee.
"The Cubs could win every game from here on out, or they could lose every game from here on out," Weeks said. "All we can do is go out and try to win games."
Joey Devine (1-0) recorded two outs in the 11th.
The Brewers broke the 1982 team record with their 217th homer, a two-run shot by J.J. Hardy in the sixth -- that was Milwaukee's first hit against John Smoltz.
Then in the 10th, Hart led off with a home run against rookie Peter Moylan to give Milwaukee a 3-2 lead. It was only the sixth homer allowed by Moylan in 75 appearances.
An even more unlikely shot came in the bottom half when Thorman, who had not homered since July 29, put Cordero's first pitch into the right-field seats. It was only the second homer allowed by the Brewers closer in 63 games.
The Brewers were at a loss even before the first pitch. Yost said ace Ben Sheets would not make his scheduled start Sunday because of a strained left hamstring. Chris Capuano, who has lost a franchise-record 12 straight decisions, will take Sheets' spot.
Yost said he doesn't know when Sheets will return to the rotation.
Milwaukee starter Yovani Gallardo gave up only three hits and two runs in seven innings to match Smoltz.
Smoltz didn't give up a hit until Hardy's two-out homer in the sixth. The Atlanta ace pitched a perfect seventh but leaned over in apparent pain after striking out Geoff Jenkins to end the inning.
Cox said Smoltz just felt a "pinch" in his shoulder that went away. Smoltz downplayed the problem, saying he is fine.
Smoltz, who was on the disabled list in early July with inflammation in his right shoulder, appeared to be trying to shake the shoulder loose earlier in the inning. He returned to pitch the eighth, and left after allowing only two hits and striking out eight.
"Smoltz was on his game," said Yost, the former Braves coach. "He looked like a 25-year-old."
The 40-year-old Smoltz is hoping for a return to the playoffs. The Braves have won seven of nine but are still also-rans in the NL East and wild-card race.
"We won," Smoltz said. "I don't care if my next game is 12-11, we want to win as many times as we can."
Jones had a sacrifice fly in the first and hit his 27th home run in the third.
Gallardo allowed only one baserunner -- on Jones' sixth-inning single -- through the next four innings.
With two outs in the sixth, Smoltz walked Weeks and lost his no-hit bid and the lead on Hardy's homer.