The Brewers, who fired manager Ned Yost with only two weeks left to go, won the NL wild card less than a half-hour later when the Mets lost to Florida 4-2. Milwaukee (90-72) and New York (89-73) went into the final day of the regular season tied.
Thousands of fans stayed in Miller Park to watch the Mets' game on the giant video board in center field, standing and cheering wildly as the Marlins recorded the final out.
Streamers and confetti fell from the rafters and fireworks went off in the outfield as interim manager Dale Sveum and the Brewers began showering each other with champagne in the middle of the clubhouse.
"I tried to visualize what this would be, and nothing could describe it," Brewers principal owner Mark Attanasio said in a television interview.
It was nice redemption for the Brewers. They blew a big lead in the NL Central last year, and were in danger of a big fold this season after going 3-11 to start September.
The Brewers will face Philadelphia in the first round of the playoffs. The NL Central champion Cubs will play the Los Angeles Dodgers.
Sabathia (11-2) pitched his NL-leading seventh complete game - those came in just 17 starts after the Brewers got the big lefty in July from Cleveland. The only run he allowed was unearned after an error by first baseman Prince Fielder, and he finished with a 1.65 ERA for the Brewers.
Sabathia struck out seven, walked one and threw 122 pitches. He got Derrek Lee to ground into a double play to end it.
The Brewers couldn't get much of anything going offensively against Cubs manager Lou Piniella's by-committee approach to pitching the final game of the regular season - until Braun's towering two-run homer off Bob Howry (7-5) broke a 1-all tie.
Conventional wisdom figured that the Brewers got a break by facing Angel Guzman instead of Cubs ace Carlos Zambrano on Sunday.
But Guzman mowed through the first two innings, giving up a leadoff single to Mike Cameron but retiring six straight, including four strikeouts.
And the rest of the Cubs' bullpen combined to keep the pressure on the Brewers. Piniella used four pitchers in the first six innings, who combined to retire a whopping 18 straight Brewers batters after Cameron's first-inning single.
Milwaukee tied the game in the seventh, but squandered a chance to take the lead.
Milwaukee's Ray Durham led off the seventh with a double off Sean Marshall, and advanced to third on a groundout by Ryan Braun.
After an intentional walk to Fielder, Michael Wuertz relieved Marshall and walked J.J. Hardy on four pitches to load the bases with one out.
Corey Hart struck out on three pitches, but Wuertz walked Craig Counsell to score a run to tie the game. Jason Kendall grounded into a fielder's choice to end the inning.
Sabathia made a stunning play in the field to end the top half of the eighth inning, barehanding a ground ball from Koyie Hill and throwing to first for the out.
Sabathia was allowed to hit for himself to lead off the eighth, and struck out looking. Cameron followed with a single.
With the crowd cheering as Florida's 4-2 lead over New York was posted on the scoreboard, Durham flied out deep. Then Braun hit the first pitch he saw from Howry into the second deck in left field, triumphantly holding his fist in the air as he rounded the bases.
Chicago took a 1-0 lead in the second, thanks in part to an error by Fielder.
With Aramis Ramirez on first base with one out, a ground ball from Micah Hoffpauir squirted between Fielder's legs, allowing Ramirez to advance to third. Ronny Cedeno then hit a potential double-play grounder, but was called safe on a close play at first as Ramirez scored.
Zambrano actually did end up making an appearance Sunday - as a pinch-hitter for Guzman to lead off the third. Zambrano, one of the best-hitting pitchers in the league, struck out swinging against Sabathia.
Sabathia nearly homered himself in the sixth, narrowly sending a long fly ball foul down the right field line.
If Sabathia was feeling any pressure Sunday morning, he certainly wasn't showing it.
Sprawled out on a couch in the Brewers' clubhouse, Sabathia boisterously debated college football with teammate Rickie Weeks and flipped through channels on a big-screen television, eventually settling on "America's Funniest Pets."
