They now move on to join the Los Angeles Dodgers in a rematch of last year's NLCS, when the Dodgers swept them in four games. It's the first time in Brewers franchise history that they made it to back-to-back Championship Series as they look to get revenge and seek their first-ever World Series title.
They are now just four wins away from reaching the World Series for the first time since 1982.
Neither team in the Brewers-Padres series ever led by more than two runs at any point. San Diego finished Game 4 with just three hits - the fewest of any of their games this Postseason - all while being held to three runs or less in three of the four games against Milwaukee.
Their quest for their first World Series title will have to wait another year, possibly more with an impending lockout on the way.
Game recap and highlights
Both teams started scoreless in the first two innings, including a 1-2-3 for each in the second. It wasn't until the third that fans saw the first run of the game.
Following a Sal Frelick single and stolen base, Garrett Mitchell earned his first RBI of the Postseason that gave the Brewers an early 1-0 lead.
San Diego responded almost immediately.
Superstar Fernando Tatis Jr. cranked a solo home run to lead off the bottom of the third as the Padres tied it up 1-1. Two of his four hits during the Postseason at that point were home runs.
Milwaukee came knocking on the door in the fourth.
William Contreras got on first with a single, ending the night for Padres starter Walker Buehler. He gave up just one run on three hits through three innings with two walks and no strikeouts.
But Robbie Ray came on in relief and got through it. He forced Bryce Turang to line out to Manny Machado at third, then surrendered a walk to Jake Bauers to put runners on first and second with one out before he struck out Cooper Pratt on a pop-up and Frelick on a force out.
San Diego went down in four batters before the Brewers tacked on their lead in the top of the fifth.
After Mitchell tripled to lead off the inning, Bradgley Rodriguez replaced Ray on the mound. But it just got worse from there. Rodriguez forced Joey Ortiz into a groundout that held Mitchell at third.
But Jackson Chourio lined one back up the middle in the next at-bat to drive in Mitchell home to make it 2-1 Milwaukee.
The RBI marked Chourio's 17th of his Postseason career, as he surpassed Brewers legend Ryan Braun (16) for the most ever at just 22 years old.
Yuki Matsui eventually replaced Rodriguez in the inning to get out of it. Aaron Ashby replaced starter Robert Glasser in the bottom of the fifth and proceeded to send the Padres batters down 1-2-3.
Glasser finished the night giving up one run on three hits with three strikeouts and one walk.
Jason Adam replaced Matsui on the mound for the Brewers, who looked to extend their lead. With runners on second and third with no outs following a ground-rule double by Pratt, Frelick hit a sac-fly to left to score Bauers from third to make it 3-1.
But Adam minimized any further damage and got out of the inning.
Nothing was happening for the Padres in the bottom of the sixth nor the Brewers in the top of the seventh. Milwaukee had the bases loaded with two outs, but stud closer Mason Miller, in his first game back off the paternity list, forced Pratt to line out to center.
Ashby finished out the seventh, going a full three innings out of the Brewers' bullpen without allowing a single hit, while giving up two walks and striking out three.
In the bottom of the eighth inning, chaos ensued as Machado had to relive history once more.
With one on and one out, Machado launched what looked to be a home run to deep center field. But Mitchell caught it over the wall in front of a reaching fan, robbing him of what would have given the Padres a one-run lead.
Abner Uribe got out of the inning without allowing a run or hit. It would have been a home run in 19 other ballparks, including Milwaukee's.
The moment was reminiscent of the 2017 World Baseball Classic when Adam Jones (Team USA) robbed Machado (Dominanc Republic) in what is considered one of the most iconic home run robberies in modern baseball.
Team USA went on to win that game, just as the Brewers did on Wednesday night.
Trevor Megill came in to close things out, sitting down the Padres lineup in 1-2-3 order without problem. They now look to get revenge on a Dodgers team and play spoiler as they eye a historic three-peat.
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