The D-backs have lost two of three games in each of their first two series at home, and things don't get any easier with the National League Central-leading Cardinals coming to town on Monday.
In each of their two wins this year, the D-backs have scored nine runs, but in the four losses, they've scored a combined five.
"It seems like we either have a real good game offensively or a bad game," Melvin said. "We've had a couple of decent games, and the rest of them, we haven't done much offensively at all."
They certainly didn't do much Sunday, though they did manage to jump out to a 1-0 lead in the first.
Felipe Lopez led off the game with a double, one pitch after Wolf thought he had struck him out on a breaking ball, and Stephen Drew brought him home with a sacrifice fly later in the inning.
Other than a pair of walks, that was all the D-backs could muster against Wolf until the eighth, when Chad Tracy led off with a bloop single to left.
In the meantime, the Dodgers managed a pair of runs, one of which came on a seldom-seen baseball rule -- the "four-out rule."
It happened in the second inning with Andre Ethier at third and Juan Pierre at second and one out with Wolf at the plate. Wolf hit a shot back at pitcher Dan Haren, who caught the ball in the air. Both Ethier and Pierre were both well on their way toward advancing and Haren turned and fired toward Lopez at second.
Rather than step on the base to force Pierre, Lopez jogged past second and tagged Pierre for what was the inning's third out. However, Ethier had crossed the plate by that point and the D-backs went on to leave the field without making a play on Ethier at third base, which would have been the fourth out of the inning.
As the teams changed sides, the umpires huddled and ruled that the Ethier run did count even without Ethier tagging up because there had been no appeal play at third base.
Melvin came out to argue, but he knew the umpires got the call right.
"I'm searching for whatever I can," Melvin said of why he argued. "Are you guys sure he didn't touch second base? Can I protest this call, or is it a judgment call? They did get it right. That's the call. They got it right. We had thought Lopez had touched second base."
For his part, Lopez was not aware that it made a difference for him to touch the base rather than the runner.
"I've never experienced a play like that," Lopez said. "It's just one of those crazy rules in baseball. I thought the guy had to go back and tag. I don't know the rule. Now I know. It's not going to happen again, [I'll] tell you that. Looking back I should have done something like [stepping on the base], but it's one of those crazy plays. I didn't know what was going on."
Even though Lopez tagged Pierre rather than the base, the D-backs still could have prevented Ethier from scoring had they tagged third base before leaving the field.
"To be honest, I still don't really understand the rule," he said. "Tough break for me to be honest. I've never seen anything like that and probably won't ever see it again. It's unfortunate, but I can't really dwell on it. I have to focus on the next time out."
Haren (0-2) went on to walk a pair and allow another run in the third, but that was all he wound up giving the Dodgers before exiting after six innings. In two starts this year, Haren has pitched 13 innings and allowed just three runs, yet he is 0-2.
"I pride myself on being consistent, going out there every time and giving my team a chance," Haren said. "I've done that, but I haven't gotten W's, but I'm where I need to be pitching-wise. You can't really measure a pitcher by wins and losses anyway. You know, there's only so much I can control."