Chase Dollander smiled in the Rockies dugout on the eve of his MLB debut.

Colorado’s ninth-overall pick in the 2023 draft will start on Sunday against the Athletics at Coors Field. Dollander, 23, is the organization’s top prospect and their next great pitching hope. The hard-throwing right-hander embraced expectations on Saturday in his first media comments since being called up to the Rockies.

“Definitely a dream come true,” Dollander said. “But as you conquer more dreams, you make new ones. So, I’m excited to start conquering those new ones.”

The decision to elevate Dollander from Triple-A was recorded on video and posted on the Rockies’ social media. The Isotopes coaching staff slowly revealed Dollander was headed to Denver. He responded by clapping and smiling with plenty of emotion.

“My first call was my mom and my stepdad. They both started crying,” Dollander said. “It’s very emotional and very exciting just knowing all the work and stuff is starting to pay off. Obviously, I still have a long way to go and still a lot of work to do, which I’m excited about. … I called my girlfriend, and she started crying as well. So, really good moments that I’ve had.”

Dollander arrived at Coors Field to find a No. 32 jersey with his name in the clubhouse.

“I feel like that’s really when it became real,” Dollander said. “Getting the call and stuff, it just didn’t feel real. Obviously, there’s a lot of excitement and stuff. But as soon as I came in the clubhouse and saw my name and the number … it was like: ‘Wow. This is it. Let’s go.”

Dollander’s quick rise to the big-league roster began with a mostly positive spring training. He posted 24 strikeouts over 17 2/3 innings. Dollander flashed his MLB-ready fastball and changeup. He also bonded with future teammates, and specifically, a member of the starting rotation.

“One person that I really leaned on was (Ryan) Feltner,” Dollander said. “He’s helped me a lot with a lot of different things.”

Feltner explained his mentorship role Saturday before the Rockies hosted the Athletics at Coors Field.

“I haven’t been around (Dollander) too much. But I tried to make sure that I’m available to him in any time of way; as a friend, as a mentor, as a pitching guru. … I don’t think I know everything. But I think there are some things that maybe I didn’t know when I came up that hopefully I can assist him with,” Feltner said. “We’ve just gone to dinner a couple of times and it’s basically just general pitching talk. … He had never pitched at elevation before. So, I said: ‘Make sure you have a way, whatever that is, to get a better grip on the ball — within the rules.’ Little things like that.”

Rookie closer Seth Halvorsen was roommates with Dollander — both University of Tennessee products — during spring training.

“First off, just a great dude,” Halvorsen told The Denver Gazette. “A great teammate and stud of a pitcher. He’s got a complete arsenal and can use any pitch in any count. I’m just really excited to watch him.”

Dollander understands the challenge of pitching at Coors Field. He said that “the ball flies here” and “stuff doesn’t move much” on pitches.

Dollander reiterated: “I’m ready for it.”

The key to success in his debut is simplicity.

“Just focus on execution,” Dollander said. “As a pitcher, there’s very little that you can control. Execution is one of them. So, just focus on that and be able to keep going.”

One of the greatest Rockies players of all time is among those most excited to see him join the team.

“Todd (Helton) texted me yesterday and congratulated me,” Dollander said. “He said he extended his stay so he could watch me pitch. Which I thought was really cool. I’m excited to see him and give him a hug.”