After all, setup men Chad Qualls and Tony Pena, along with closer Brandon Lyon, each gave up runs.
A closer examination, though, shows that Arizona really lost this one much earlier. At the plate, the D-backs could not cash in plenty of scoring opportunities, and on the bases they ran themselves into a pair of outs.
"They got some big hits when they needed it," manager Bob Melvin said. "They didn't miss with runners in scoring position, and the deciding factor was they got big hits and we left a few guys out there."
Arizona left 12 to be exact, including seven in the first three innings. It was because of that, along with Stephen Drew and Chris Young getting thrown out on the bases, that the D-backs led just 2-0 after five innings despite outhitting the Brewers, 8-2.
"We had a lot of hits early on and good at-bats, we just couldn't push across a crooked number," Melvin said. "We had plenty of hits."
Arizona pushed across its first run in the second inning when Miguel Montero hit a liner that glanced off the glove of diving second baseman Craig Counsell and bounced into center field for a hit that scored Chad Tracy.
Young tried to score on the play as well, but Counsell was quick to field the ball in shallow center and cut Young down with a perfect throw to the plate.
That was the lone run the D-backs were able to get that inning as Brewers starter Seth McClung was able to get Drew to line out to left to leave the bases loaded.
One inning later, Young's two-out single gave Arizona a 2-0 advantage.
While the D-backs didn't take advantage of what was given to them, Yusmeiro Petit simply wasn't giving the Brewers any opportunities.
Petit, who got the nod in place of the injured Micah Owings, certainly deserved better than a no-decision in this one. The right-hander threw his fastball, curve, slider and change for strikes and that allowed him to keep the Milwaukee hitters guessing through six innings.
The lone run allowed by Petit came in the sixth when J.J. Hardy stroked a two-out single to left to score Jason Kendall.
"He was pounding the strike zone," Montero said. "He got ahead in the count and that was the key right there."
Things would begin to unravel in the seventh. After lefty specialist Doug Slaten retired the first two hitters in the inning, Qualls allowed a triple to Gabe Kapler and an RBI double to Mike Cameron to tie things at 2-2.
"The one mistake I seem to be making, they're putting the ball in play and making me pay for it," said Qualls, who has struggled of late. "It's just a matter of going out there and making better pitches. That's all there is to it. Obviously, the pitch to Cameron wasn't a very good pitch, but I went back and looked at the video, and the first-pitch slider to Kapler I thought was a pretty good pitch down and away."
Pinch-hitter Rickie Weeks led off the eighth with a homer off Pena on an 0-2 fastball that was supposed to be outside, but instead was slightly up and right down the middle of the plate.
Justin Upton tied the game with a homer of his own in the bottom half of the inning and it seemed like maybe the D-backs had momentum going their way.
The top of the ninth opened with a fielding error by Mark Reynolds, who was playing first base for the first time in his Major League career, putting Russell Branyan on first. After a sacrifice moved Branyan to second, he scored when Cameron lined a curve ball into left-center.
"It doesn't matter, it's a ground ball," Reynolds said of being at first base for the first time. "I've got to make the play. That's all I've got to say."
The D-backs fell to 42-43, the first time they've been under .500 since April 3 when they were 1-2. They still hold a 1 1/2 game lead over the Dodgers in the National League West. The division is 53 games below the .500 mark collectively.
Steve Gilbert is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.