On Friday night, it was Kevin Mulvey. This time, it was Max Scherzer.
"I wasn't able to get ahead of hitters, and that's what cost me," Scherzer said. "I ended up walking five guys, and walks will always kill you."
Just three pitches into the game, the Rockies had a lead, as Carlos Gonzalez blasted a solo homer, and two outs later, Troy Tulowitzki hit one of his own to give Colorado a 2-0 lead.
Scherzer did settle in during the second and third innings and his teammates gave him a lead when Justin Upton blasted a three-run homer in the third, his 25th of the year.
The lead didn't last, though, as the Rockies scored a pair in the top of the fourth to go back on top, 4-3.
One of the runs in the inning was unearned thanks to an error by Gerardo Parra, who threw wildly trying to nail Tulowitzki at the plate on Ian Stewart's sac fly.
"He's got such a good arm that he tries to make too many plays," D-backs manager A.J. Hinch said of Parra.
Scherzer's night came to an end in the sixth, when he walked back-to-back hitters with one out.
When Scherzer has struggled this year, it's been when he has fallen behind in counts and therefore seen his pitch count rise early in a game.
"Five walks in five-plus innings is too many," Hinch said. "He fell behind too many hitters, had deep counts and never really got on the offensive side of pitching and was pitching from behind quite a bit. That's a difficult task against a good club."
Scherzer was at a loss to explain the bout with wildness.
"I wish I could tell you what it was," he said. "I was in 2-0 counts and just trying to give them a pitch to hit and see how far they could hit it, and I was missing still."
A run in the eighth courtesy of Upton's sacrifice fly pulled the D-backs to within a run.
Any comeback hopes were dashed in the ninth when the Rockies scored five times.
The inning started off inauspiciously for Arizona, when reliever Esmerling Vasquez walked Dexter Fowler after jumping ahead 0-2.
"Vasquez has been sensational since the All-Star break, but to get 0-2 and then lead to a walk to lead off the ninth is just a recipe for disaster," Hinch said.
And that's just what it led to.
Ryan Spilborghs and Yorvit Torrealba added RBI hits, and with two outs and two on, Hinch brought in lefty Scott Schoeneweis to face pinch-hitter Jason Giambi.
On the first pitch, Giambi lined a fastball into the seats in right for a three-run homer and a 10-4 Colorado lead.
"I thought we had some decent momentum after the eighth, and they just simply took us out of the game in the ninth," Hinch said. "The poor execution of pitches is haunting us right now. They just continued to get the next hitter up to bat and we never could stop them."