With the loss, the D-backs fell behind the Rockies in the standings and into last place in the National League West. It is the first time since July 13 that the Rockies have been out of the NL West cellar.
Anderson was called up from Double-A Mobile in May and quickly became a mainstay in the rotation.
"Overall a very good year," D-backs manager Kirk Gibson said of Anderson. "He'll have time to think about this year and look forward to next year."
With his innings total far surpassing that of last season's mark of 88, the D-backs decided that Friday's start would be his final one of the season. In going five innings, Anderson raised his season total to 114 1/3 in the big leagues with another 39 at Mobile.
"I'm healthy," said Anderson, who battled injury issues in the past in the Minors. "I finished the year strong, the velocity was up there tonight. I'm just thankful to be in this position, to be in the big leagues."
The D-backs gave Anderson a 1-0 lead in the first inning and he cruised through the first three innings.
Things spun out of control for him, though, after that as the Rockies scored three runs in the fourth and another three off him in the fifth. With Gibson's decision to leave Anderson in the game to take the pounding, his ERA ballooned from 3.70 at the start of the game to 4.01.
"The first three innings were pretty quick for me," Anderson said. "I kept attacking the zone. I probably should have expanded a little more once I got ahead to put those guys away. I've just got to learn to make that adjustment within the game. When I'm throwing a lot of strikes, I'm feeling good and get ahead -- that's when I've just got to put the hitter away and just keep going and going."
Things would get worse for the D-backs after Anderson departed as the Rockies scored five runs off reliever Eury De La Rosa in the sixth.
"They had a good approach up the middle," Gibson said. "They lead the league in hitting and they showed why tonight."
The big blow of the inning was delivered by Michael Cuddyer when he hit the eighth grand slam of his career in the sixth inning.
"He's been hurt all year but when he's been out there, he's shown he's still an elite hitter in this game," Rockies manager Walt Weiss said. "He's probably one of those guys who will be able to hit until he's 50."
Cuddyer also had a pair of doubles and drove in a career-high seven runs.
"He's been around a long time and he's a very solid ballplayer," Gibson said.
Jordan Lyles picked up the win for the Rockies as he allowed just two runs while scattering nine hits over six innings.
The Rockies tacked on four runs in the eighth for good measure off reliever Joe Paterson.