MILWAUKEE -- No matter how many runs the Cardinals scored, Game 2 only counts as one loss against the Brewers in the National League Championship Series.

That's the good news for Milwaukee. The bad news is that in one of the most important games of the season, the Brewers played one of their worst.

But while it got ugly late as St. Louis added five runs to an already-sizeable lead, the 12-3 loss counts no differently for Milwaukee than if it had been 5-3 or 7-3.

"A loss is a loss at this stage," said Brewers third baseman Jerry Hairston Jr. "In this game, things happen. You're going to take it on the chin. But we realize we didn't go undefeated throughout this season here at home."

The nine-run margin was the most lopsided loss at home in 2011 for the Brewers, who have gone 61-25 at Miller Park this year, including 4-1 in the postseason. Their biggest loss previously was a 13-6 defeat on May 11 at the hands of the Padres.

Just as in Game 1 of the NLCS, Milwaukee trailed 5-2 in the fifth inning Monday night. The difference is, instead of being the inning when the home team turned things around, the fifth was the frame when the Brewers let the game get away from them.

After cutting the lead to just three runs in the bottom of the fourth, reliever Marco Estrada allowed a pair in the fifth to put it right back at a five-run ballgame. Two innings later, Kameron Loe couldn't stop the bleeding as he allowed four runs on six straight hits.

But Milwaukee only scored one more run, so even five runs could have been enough for St. Louis.

"It wasn't joyful," said Brewers slugger Prince Fielder. "But you've got to deal with it and move on."

With the loss, the Brewers dropped to just 1-5 all-time in Game 2 of postseason series. The only time they won the second game of a series was a week ago, in the NL Division Series against the D-backs.

They have won a series before when losing Game 2, though.

In 1982, Milwaukee won the only pennant in club history as it took the American League Championship Series in five games over the California Angels after dropping both of the first two games on the road.

With the loss Monday, the Brewers now will need to avoid repeating what they did in the NLDS -- in which they lost both road games -- and pick up at least one win on the road.

And while Milwaukee was much better at home than on the road this season, the NL Central champs were also much better on the road in the second half than they were before the All-Star break.

"Oh, I feel fine. It's nice to kind of get everything out of the way today," said Brewers manager Ron Roenicke. "We didn't play well today. We didn't play well defensively. We didn't pitch well. I thought we swung the bats OK.

"But going into St. Louis, hey, we're going to have to keep swinging the bat well. We need to pitch better. It's nice we have [Yovani Gallardo] going. We feel real confident with that. And we'll see what happens."