MILWAUKEE -- The crowd of 15,347 that left Miller Park late Thursday night must have been asking, what happened?

What happened to the Brewers who won five of six games here to open the franchise's most promising season in a decade? The Brewers that returned home on Thursday looked nothing like that ballclub, blowing a four-run lead in a mistake-marred, 12-8 loss to the Cincinnati Reds.

So what happened? It was pretty simple to manager Ned Yost.

"Our pitching stunk," said Yost, his voice raised after his club lost for the eighth time in its last 11 games. "That's all it is. We just didn't pitch good."

Bill Hall and Prince Fielder scored two runs apiece and Brady Clark had two RBIs by the end of the third inning as Milwaukee built a 6-2 lead. But starter Tomo Ohka and the Brewers bullpen surrendered 10 runs over the next three innings as the Reds pulled away.

In all, Ohka, Justin Lehr, Jorge De La Rosa and Mike Adams surrendered 12 runs, 10 of them earned, on 11 hits, seven walks and three home runs in just the first six innings.

"We have a good bullpen. It's definitely not a bad bullpen," said Adams, who surrendered the game's biggest blow, a sixth-inning grand slam by Reds second baseman Brandon Phillips. "Some of the guys are a little overworked down there, and I think that's contributing a little bit to the way some guys are throwing."

Adams admitted that he's not one of those guys. The right-hander, who started last season as the team's closer, just joined Milwaukee earlier this week in Houston. In two outings, Adams has allowed three runs on four hits over 2 1/3 innings.

"I threw a slider that sat a little bit, and he took a good swing on it," Adams said.

He was not the only Brewer victimized by one pitch. Phillips, Cincinnati's No. 8 hitter, who entered the game homerless in 25 at-bats, also hit a two-run home run off Ohka in the fourth inning. Encarnacion had three RBIs for the visitors, including a go-ahead, two-run homer off Lehr (0-1) in the fifth.

Brewers relievers now have a 4.84 ERA in 48 1/3 innings of work this season. As recently as Sunday, the Brewers led the Majors with a 2.27 bullpen ERA, but in the five games since, Milwaukee relievers have been tagged for 26 earned runs and 21 hits in 16 1/3 innings for a 14.44 ERA.

"Over the last couple of games we haven't really pitched well, with the exception of Capuano's game," Yost said, referring to Chris Capuano's 7 2/3-inning start on Wednesday in Houston. "Those things all turn around. The pitching will get back on track."

The Brewers could potentially get a boost on Friday, when Dan Kolb is expected to return to active duty after missing a week with a stiff right elbow. The other bright spot on Thursday was right-hander Chris Demaria, who, like Adams, was called up earlier in the week and delivered two scoreless innings on Thursday in which he did not allow a hit and struck out three.

"They're hanging in there," bullpen coach Billy Castro said of his relievers. "They've had a lot of work."

Thursday's game, and most of the past week for that matter, marked a reversal from earlier games when the Brewers were getting good pitching and solid defense, but were struggling to collect clutch hits.

This time, the offense was there, but the pitching and defense were not. J.J. Hardy, Hall and the red-hot Fielder had three hits apiece, and veteran catcher Damian Miller continued to climb out of an early funk with a pair of doubles. Seven different Brewers, including Ohka, drove in at least one run.

"It's still early," said second baseman Rickie Weeks, who extended his hitting streak to nine games. "We still have time to get everything situated. You just hope we get it situated sooner [rather] than later."

The Brewers also committed two more errors on Thursday -- they have at least one in 12 of their first 16 games this season -- and gave away at least three of the Reds' runs on various miscues. Weeks and Fielder were unable to connect quickly enough on Ryan Freel's routine grounder leading off the first inning, and Freel later scored. Ohka's throwing error allowed a run to score in the fourth and Adams walked home a run with the bases loaded in the sixth.

The Brewers managed to bring the potential tying run to the plate in the eighth inning, but Weeks and Fielder both struck out with the bases loaded.

"We made some mistakes that hurt us," Yost said.