The Rockies are expected to officially announce their 25-man roster Saturday.
"In the final analysis, we felt like Franklin came in and won that spot by the way he pitched," Rockies manager Walt Weiss said.
Morales has come a long way. He made his debut with the Rockies in 2007 and was a starter with Colorado until 2009, when former Rockies manager Jim Tracy made him a reliever. Morales was eventually sold to the Red Sox in 2011 and pitched primarily out of the bullpen during his time in Boston.
"Frankie is a great competitor and he's pitched in a lot of big games in his career. World Series with us in '07 and with the Red Sox, so he's been on the biggest stage in the game," Weiss said. "He can still throw. He's still relatively young even though he's been around. There is still a lot of life in the arm and he's shown that this spring."
In all, Morales has just 25 starts in 195 big league appearances, the most coming in 2012 when he made nine starts for the Red Sox. He made a bid for Boston's starting rotation last year but was slowed by injuries during Spring Training and returned to the bullpen. Morales was traded back to Colorado in December.
"He's got more weapons to attack those guys with than he did the first time around with us, when he was a hard-thrower with a big breaking ball," Weiss said. "Now, he's able to get in on right-handers' hands with that cutter and speed them up, and go to the split-finger to get them out. He's more of a pitcher now than he was the first time around."
As for Lyles, he was charged with six earned runs on 18 hits in 17 Cactus League innings. He struck out 12 batters and walked six. Kahnle gave up one run on four hits in 9 2/3 innings this spring.
"We felt like Frankie, at this point in time, gives us our best shot as a starter," Weiss said. "Jordan is going to be a big part of this club this year and well beyond. We really like Lyles and we feel like he's really accomplished some things this spring mechanically. He's starting to get all of his weapons in order. We really like Jordan."
The club also placed right-handed pitcher Jhoulys Chacin, who has right shoulder strain, and left-handed pitcher Boone Logan, who is suffering from left elbow inflammation, on the 15-day disabled retroactive to March 21.
Weiss also confirmed the Rockies will carry six outfielders on the Opening Day roster. Left-handed-hitting outfielders Charlie Blackmon and Corey Dickerson are expected to join Carlos Gonzalez, Michael Cuddyer, Drew Stubbs and Brandon Barnes.
"I felt like all those guys bring something that will help us win games," Weiss said. "It's a little unorthodox by design and I'm not sure how long we will be able to sustain it, but it gives us a lot of weapons, particularly later in games. These things have a way of working themselves out."