Rickie Weeks hit a leadoff homer to begin Carpenter's miserable outing, and the Milwaukee Brewers capitalized on perhaps the St. Louis Cardinals' shakiest defensive inning of the season in a 12-5 victory Saturday night.
"I didn't pitch well enough for us to win, no matter what we did offensively or defensively," Carpenter said. "When you put your team down 8-0, it's not going to give them a whole lot of hope."
Carpenter (9-2), among the Cardinals' hopes to land an All-Star spot, failed to retire any of the four batters he faced in the fourth. Carpenter was charged with eight runs -- seven earned -- in his shortest outing since April 14, 2009, when he lasted three innings at Arizona before injuring a side muscle that landed him on the 15-day disabled list.
"Days like this are few and far between for a pitcher of his caliber," said Ryan Braun, who had three hits and two RBIs. "He's one of the best and we were just happy to get some runs off him."
Carpenter was struck on the right forearm by a line drive in his last start, but said he was fine earlier in the week and stayed on his turn. Before Saturday he had been 15-1 with a 1.97 ERA against the NL Central the last two seasons.
"I wouldn't go out there if I had an opportunity to hurt myself," Carpenter said. "My arm was fine."
All the Brewers knew for sure was that Carpenter was hittable.
"Who knows what condition his arm was in," manager Ken Macha said. "He's a tremendous pitcher, best in the league. We had some balls that blooped in and some balls hit hard. They threw the ball around a little bit."
Cardinals manager Tony La Russa met with unspecified players after the game and began his postgame news conference 18 minutes after the game ended.
"I hate to say it was one of those days, but it was," La Russa said. "We just did not play well defensively."
Jim Edmonds homered among his four hits and had three RBIs, and Corey Hart singled twice to extend his hitting streak to 18 games. Manny Parra (3-5) had two hits and an RBI and Ryan Braun had three hits and two RBIs for Milwaukee, which had the bases loaded in the second, third, fourth and fifth. The Brewers scored in the first five innings while building an 11-0 cushion.
"It was a good day," Parra said. "Got two hits, got hit by a pitch, we won."
Albert Pujols homered for the fifth time in seven games in the fifth, but the Cardinals were trailing 11-2. Pujols grounded into an inning-ending double play with the bases loaded to end the third when Milwaukee was up 6-0.
Defense was the bigger issue for St. Louis, which committed two errors and could have had a third in a four-run third. The Cardinals left the field to boos from a sellout crowd of 43,276 -- also attracted by a huge fireworks display on the riverfront.
Shortstop Brendan Ryan threw wildly to the plate on Alcides Escobar's RBI infield grounder, allowing runners to move up. Rookie second baseman Tyler Greene whiffed on a one-hop relay after George Kottaras' sacrifice fly, allowing a second run to score when the ball dribbled into the infield.
Ryan also bobbled a high throw leaping at second for Nick Stavinoha's throw from right in a forceout attempt after Braun dropped in a bloop hit. Earlier, Greene, a minor league callup Friday who had played only shortstop the previous month at Triple-A Memphis, overran catcher Yadier Molina's throw on Edmonds' steal in the second and tumbled to the dirt before he could make the tag.
Weeks hit his fifth leadoff homer and 14th of his career on Carpenter's second pitch of the game. Carpenter proceeded to strike out the next three hitters on only 12 pitches, but hit Parra and Weeks in succession in the second to force in a run.
Hart singled twice and is batting .364 (28 for 77) with a homer and 18 RBIs during the longest active streak in the majors.
Carpenter has hit 10 batters, tied with Atlanta's Tommy Hanson for the NL high. He has allowed 14 homers, twice as many as all last season, although 10 have come with the bases empty. ... Weeks has 14 homers and 49 RBIs, best among the majors' leadoff hitters. Weeks was hit by a pitch twice, and leads the majors with 15. ... Cardinals pitchers gave up a season-high 19 hits. ... The Brewers' Joe Inglett leads the majors with 11 pinch hits after doubling in the eighth.