The strong, 23-year-old right-hander threw six sharp innings Wednesday as the Rockies won a series against Arizona for the first time in two years.
But as had been determined before the game, Morales was optioned to Triple-A Colorado Springs to make room for right-hander Jason Hammel, acquired Sunday in a trade with Tampa Bay.
"I don't think about all that," Morales said. "I try to do my job. It's not my decision, you know. I've got to go down and keep pitching."
Morales allowed one run and four hits, struck out six and walked one. After the game, he said his performance came 18 years to the day since his father was killed in a car accident.
Colorado manager Clint Hurdle praised the youngster's effort.
"Very efficient, never really got out of sync with anything, stayed around the plate," Hurdle said. "One walk, six punchouts, so it was just what we needed today, just what the team needed and just what Franklin needed."
After homering five times in their 9-8 season-opening victory on Monday, the Diamondbacks followed with two runs in two games against the Rockies, who were 3-15 against Arizona last season.
"The last two games we were able to make some adjustments," Hurdle said. "We gave up two runs in 18 innings against a club that had their way with us last season."
Stephen Drew had a solo home run for the Diamondbacks in the first.
"It's frustrating to lose two out of three at home," Drew said, "but we're going to look forward to Friday, Saturday, Sunday, take tomorrow off to think about some things and get back after it."
Fowler hit his first major league home run on the first pitch of the game from Doug Davis, sending it into the seats in left-center. He said he was looking for a fastball and got one.
"I was just trying to drive the ball up the middle -- awesome," Fowler said.
Torrealba and pinch-hitter Stewart hit back-to-back drives off Billy Buckner in the seventh to put Colorado ahead 6-1.
Davis (0-1) allowed four runs and four hits in five innings. He struck out four and walked four.
Morales and Jason Grilli combined to retire 12 in a row from the fourth through the seventh inning.
"Just an ugly game," Arizona manager Bob Melvin said. "We probably didn't make Morales work as hard as we should have, and then as the game went along it got worse for us."
There were, however, a few slick defensive plays. Arizona shortstop Drew threw from his knees and first baseman Conor Jackson made a nice stretch to rob Torrealba and end Colorado's third inning.
Center fielder Fowler, who was busy all day chasing and catching flyballs, made a nice running catch of Drew's sharp line drive in the fifth.
The crowd of 18,277 was only 97 more than the Diamondbacks' smallest at home in their history.
- Arizona RHP Max Scherzer will start Thursday for Class A Visalia at Lake Elsinore. Scherzer is on the DL because of a sore shoulder earlier in the spring. He is expected to make his first Diamondbacks start against St. Louis next Tuesday.
- All six of Colorado's home runs in the series were solo shots.
- RHP Jason Marquis will get the start in Colorado's home opener Friday night against Philadelphia. RHP Jon Garland will make his Arizona debut Friday night at home against the Los Angeles Dodgers.