One of the oft-used axioms when it comes to player development is that the leap from Single A- to Double-A is the toughest one to make. Zac Veen, the Rockies' top prospect, found out just how true that can be.

The No. 9 overall pick in the 2020 Draft spent the bulk of his second full season with High-A Spokane and put up solid enough numbers to get kicked up to Hartford for the final 34 games of the season. The 2022 Futures Gamer and No. 24 prospect on MLB Pipeline’s Top 100 found the move to the Eastern League, and the pitching he faced, to be tough sledding.

“I’d say it’s much more refined,” said Veen, who hit .177/.262/.234 in 124 Double-A at-bats. “You have to have a lot more discipline. It’s an adjustment to make, but it will be made.”

Even with the struggles, the 20-year-old outfielder points to getting that experience as one of the biggest highlights of his year. And he’s hoping some of the things he learned can carry over into his time with the Salt River Rafters in the Arizona Fall League.

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“Ultimately, it's the same game, it’s just a bit bigger of a stage,” Veen said of the climb. “I’m just learning how to control myself in that environment and how to adjust each day.

“A lot of the guys that I played in that league are in the Fall League. I think it's always good to go against the best talent in the world.”

If early returns are any indication, Veen is making some of those adjustments. He’s off to a 6-for-12 start over his first four games in the AFL with a homer, a double and four RBIs.

He also has four stolen bases, which should no longer come as a surprise. While he had more of a reputation as a left-handed hitter with considerable power potential as he entered pro ball from the Florida high school ranks, Veen has shown he is not afraid to run as a pro, stealing 36 bases in 53 attempts in his first full season, then upping that to 55 (in 64 attempts) this past year.

“I knew I just wanted to go if I had the jump and it was there,” said Veen, who felt that the rules in A ball that limited pickoff moves didn’t make it easy to run. “I didn’t want to get thrown out at all. I definitely took that from last year and wanted to show my baserunning a little bit more.”

While Veen did hit 12 homers in 2022, all but one with Spokane, the stolen-base totals could lead to him being seen solely as a speedster. But it’s clear he wants to be more than a one-trick pony.

“I want to be known for all of it,” Veen said.

Rockies hitters in the Fall League

Warming Bernabel, 3B (No. 8): One of the youngest players in the AFL this year, Bernabel is coming off a big season in which he produced offensively across two levels of A ball. The 20-year-old hit a combined .313/.370/.499 with 14 homers and 23 steals. His time with Salt River will get him ready for the upper levels as he continues to learn to refine his super-aggressive approach.

Grant Lavigne, 1B (No. 13): Taken out of the New Hampshire high school ranks in 2018, Lavigne struggled in his first full season as he sold out for power too much. He got back on track some in 2021 and reached Double-A this year as he continues to find the balance between his advanced approach and feel while tapping into his raw power from the left side of the plate.

Braxton Fulford, C: A Texas Tech product taken in the sixth round of the 2021 Draft by the Rockies, Fulford is on the Salt River taxi squad to provide some catching depth. He’s a solid backstop who spent his first full season with Single-A Fresno, hitting 15 homers and stealing 13 bases while throwing out 36 percent of potential basestealers.

Rockies pitchers in the Fall League

Blair Calvo, RHP: The Rockies signed Calvo as a 23-year-old senior out of Flagler College for just $3,000 in the 23rd round of the 2019 Draft. Moved to the bullpen after signing, he spent 2022 in Double-A and struck out 12.1 per nine in 35 innings at that level.

Fineas Del Bonta-Smith, RHP: Noah Davis was supposed to head to the AFL, but when he got called up, the Rockies replaced him with Del Bonta-Smith. A 22nd-round pick in 2019 out of San Jose State, the right-handed reliever spent most of the 2022 season in Double-A and struck out a combined 10.3 per nine. He needs to work on keeping the ball in the ballpark as he allowed 11 homers in 57 total innings.

Stephen Jones, RHP: Another late-round 2019 draftee (21st round), Jones was Samford’s closer in his Draft year and he’s continued to relieve in the Rockies system. The 6-foot-4 right-hander picked up eight saves with Double-A Hartford this season, striking out 10.4 per nine and holding hitters to a .188 average.

Peter Lambert, RHP: Lambert made 19 big league starts in 2019, then had Tommy John surgery in July 2020. He did return for a couple of outings in 2021, but elbow issues limited him to just 8 2/3 Triple-A innings this year. A one-time top-five prospect in the system, Lambert is trying to get back on track and get some innings this fall with an eye on returning to Coors Field in 2023.