Brewers starter Shaun Marcum provided an unexpected lift at the plate. His bullpen did nothing to help him after he departed.
Marcum only the second grand slam by a pitcher in franchise history and first in nearly 42 years, but the Brewers squandered a five-run lead for the second straight day when the Arizona Diamondbacks scored seven unanswered runs in an 8-6 victory over Milwaukee on Monday.
The Brewers blew a similar 6-1 lead against the Twins on Sunday.
"Anytime you lose games that you think you should win, it does a little something to you. If it happens a lot of times, it ends up mentally bothering you," manager Ron Roenicke said. "I think it's important when we have these leads, we've got to close them out."
They certainly had plenty of chances.
Milwaukee had just come off a 1-5 road trip that had Roenicke disappointed because they hadn't played the same as at Miller Park, where they're an impressive 29-12 this season.
This meltdown was just as bad after Milwaukee appeared to be rolling even without Ryan Braun, who missed his second game with a strained left calf.
"I think it's a bad stretch coming off the road trip," Roenicke said. "We didn't swing the bat well, we didn't pitch well on the road and that's been happening, but usually when we come back here, we usually play well."
Marcum, who spent his first five seasons in the AL with Toronto before coming to Milwaukee in an offseason trade, received a curtain call and tipped his batting helmet to the sellout crowd of 41,622.
That would be the last offensive highlight for the Brewers.
Sam Demel (2-2) earned the win with a perfect eighth inning.
Marcum gave up four runs and left with a 6-4 lead after the sixth.
"When I get hit hard, I mislocate pitches or the ball's up in the zone and that's what happened," Marcum said. "The ball just didn't seem like it was coming out off my hand like it was early on. I don't know if it was because of a long inning or what, but it didn't seem to have that extra life like it had early on."
In the seventh, reliever LaTroy Hawkins gave up a run-scoring single to Stephen Drew that cut it to 6-5. The Diamondbacks tied it at 6 in the eighth off Kameron Loe despite getting two runners thrown out at third. First, Miguel Montero was thrown out trying to take the extra base, then Juan Miranda did the same after his run-scoring double.
That set the stage for the ninth.
Kelly Johnson hit a bunt single off Brewers closer John Axford (2-2) and reached second on a wild pitch. With two outs, Young laced a single to left field to put Arizona ahead 7-6. Young stole second and reached third on a throwing error on the play. Montero singled him in for the final margin and snapped Axford's string of 17 consecutive save conversions.
"Everyone's still positive," Axford said. "I don't feel I'm putting any more pressure on myself and I don't think anyone else here is, either."
NOTES: RHP Fred Talbot hit a grand slam for the Seattle Pilots on July 11, 1969, against California. The Pilots moved to Milwaukee before the 1970 season. ... It was the 12th sellout at Miller Park this season. ... Marcum joins Zack Greinke and Yovani Gallardo as Brewers' pitchers to record a homer this season. The last time three pitchers homered in a season for the Brewers was 1970. ... Brewers 1B Prince Fielder has three errors in his last four games.