Melvin was especially encouraged when the D-backs scored 11 runs against the A's on Wednesday.
"I really thought after the game against Oakland, where we put up a lot of runs, that we were on our way and that we had loosened up a bit," Melvin said. "But we haven't been able to do it on a consistent basis."
Since that outburst, the D-backs have scored five runs in three games and they are struggling to draw walks as well. In their past seven games, they've walked 11 times and struck out 54.
"I think, at times, when you're not scoring and you're struggling a little bit, you get anxious at the plate," Melvin said. "If you're striking out some, you don't want to get into those counts where you have two strikes and a little bit of anxiousness sets in, so I think that may have something to do with it."
It's certainly something that has taken its toll inside the D-backs clubhouse.
"It's miserable," Melvin said. "Especially after the way we started, expectations are high, guys expect to do well, and to go through prolonged periods of it is very frustrating."
And still the manager remains firmly behind his team.
"I'm still confident that we will turn it around," Melvin said.
Steve Gilbert is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.