MILWAUKEE -- While the bullpen had plenty to do with the early-season success of the Pirates, the unit finally cracked in a big way on Monday night.

In a game that had all the makings of an inspiring comeback, the Bucs' bullpen opened the floodgates with a five-run eighth inning in suffering a 10-5 loss against the Brewers at Miller Park.

The Pirates (11-8) suffered their 16th consecutive loss -- dating back to the 2007 season -- at Miller Park.

After the Pirates tied the game at 5 in the eighth inning on a two-run double from Freddy Sanchez, the bullpen couldn't ride the momentum. Tyler Yates (0-1) allowed three earned runs without giving up a single hit in just one-third of an inning before John Grabow was touched for two runs on two hits while retiring only one batter.

Yates walked leadoff hitter Bill Hall on five pitches, hit Jason Kendall with the pitch and gave up a sacrifice bunt to Craig Counsell. With runners at second and third, Rickie Weeks delivered the go-ahead run on a fielder's choice.

Grabow then entered and served up an RBI double down the right-field line by Corey Hart, a two-run single up the middle by Prince Fielder and a sacrifice fly from Mike Cameron. Just like that, the Brewers built a commanding 10-5 lead, in what just moments before, was a tie game.

"We brought in guys that we rely on heavily all the time," Pittsburgh manager John Russell said. "They just didn't get it done tonight. Tyler and John are two guys we'll go to every time in that situation. Most times they come through alright. It was just one of those nights."

The Brewers (9-10) hurt the Pirates early with the home run ball. Pittsburgh starter Jeff Karstens lasted just five innings and left the game with a three-run deficit. Making his third start of the season, Karstens took the mound with a 2-0 lead only to give up home runs in each of the first three innings.

Brewers slugger Ryan Braun belted a long, solo home run to right field in the first inning, Weeks added a three-run shot in the second and Cameron delivered a solo homer in the third. Pittsburgh added one run in the fifth on an RBI single from Eric Hinske and tied the game in the eighth on a clutch, two-out blooper to left field from Sanchez.

Milwaukee reliever Todd Coffey (1-0) then entered and faced only one batter, striking out Craig Monroe and stranding Sanchez at second base to end the Pirates' rally in the eighth. It was a new game, tied at 5, before the typically reliable Pirates bullpen caved in. Pittsburgh relievers entered the game second in the National League with a stingy 2.85 ERA.

"I wasn't in a rhythm at all," Yates said. "The first batter I struggled finding the strike zone with my fastball. For me, that's a big part of attacking hitters with my fastball and putting them away with the slider. I fell behind and started guiding the ball instead of just letting go and trusting my stuff. I committed the cardinal sin in walking the first batter I faced."

The Pirates plated a pair of runs in the first on a leadoff walk from Nyjer Morgan, three straight singles from Sanchez, Monroe and Adam LaRoche and a fielder's choice by Hinske.

The game became heated at the start of the third inning when Karstens drilled Braun right between the numbers on the very first pitch. Braun, who had earlier hit a laser shot over the left-field wall, stared back at Karstens and both benches were quickly warned.

Braun was still upset with the pitch after the game.

"It's rare for Major League pitchers to miss that much with a fastball," Braun said.