Kala'i Rosario just turned 21 in July, so it’s hard to believe his professional career started over three years ago. And like for so many from the Draft class of 2020, it wasn’t clear if and when it was going to start.

A high schooler from Hawaii, Rosario had his high school season cut short and then found out the Draft was just five rounds. There was some definite uncertainty.

“I wasn’t nervous, but just the fact that it was only five rounds and getting drafted was my No. 1 goal,” he said. “I wanted to get to pro ball and get out there. I’ve been having fun my whole life doing this, and I felt like pro ball was the next step that I’d love to do. It was a crazy day, but I got drafted by the Twins and I couldn’t ask for anything better.”

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It took a while for Rosario, the No. 19 Twins prospect, to get up to speed. He remembers being 17 and at instructs, the first pro baseball activity he was allowed to do during the pandemic. He was overwhelmed at times, challenged by trying to acclimate while playing alongside much older players.

“The organization helped me a lot with my development and put it in my head, you don’t need to do all this in one year, you have time to develop,” Rosario said. “It was good, but a tough transition for me.”

His development has indeed been slow. After making his official debut in 2021 in the Rookie-level Florida Complex League, Rosario put up so-so numbers in full-season ball in 2022 (.727 OPS). This year things started to click for him. The 21-year-old always had a power-over-hit profile, but he started getting to that pop more consistently, leading the Midwest League with 21 homers and setting the stage for him to go to the Arizona Fall League to prepare for the upper levels. It all came about through some assistance from Hawaiian baseball royalty.

"Throughout the offseason, I took my work very seriously,” Rosario said. “I came out to Arizona really early, trained with Kolten Wong and Kean Wong.

“Kolten has been in the big leagues for 10 years. Kean has big league experience and a lot of Minor League experience. I’m in the cages with them every single day. They’re not changing my swing on every little thing, but the knowledge that they share, I was just soaking it all in. And I’d say my work ethic progressed. I carried that throughout the year.”

Rosario still swings and misses too much, and while he has three home runs over his first 11 games, he has struck out in 31.1 percent of his plate appearances in the AFL as of Wednesday. His walk rate did jump in 2023 and his K rate -- still high -- went down compared to 2022. He knows he’s still a work in progress, with pitch recognition a key to future success.

“I feel like every year in pro ball, I had small little things I needed to work on,” Rosario said. “I feel like I didn’t try to go at it, like I had to do everything at once. This year, I feel like the second half of the year, maybe pitchers pitched me a little bit different. I’m going to take that into next year. I feel like me struggling this year with certain pitches is going to help me next year.”

Twins hitters in the Fall League

Andrew Cossetti, C: A 2022 draftee, Cossetti had a solid first full season with the bat, putting up a .287/.426/.534 line across two levels of A ball. He made some strides behind the dish and his defense is a continued area of focus this fall.

Aaron Sabato, 1B: The Twins’ first-round pick in 2020, Sabato has had difficulty gaining traction. A lot of that has to do with his approach and tendency to swing-and-miss (32 percent career K rate), something he’ll keep working to cut down with Glendale.

Twins pitchers in the Fall League

Malik Barrington, RHP: Barrington played his college ball at Albany State then went to indy ball before signing as a free agent in July 2021. He misses bats (11.1 K/9 with Cedar Rapids this year) especially with his breaking stuff -- a slider and a curve that are similar with the former just being a bit more sweepy -- but he needs to throw more strikes (5.5 BB/9 in 2023) to have a chance at the upper levels.

Jordan Carr, LHP: Another indy ball signee in 2021, Carr is a southpaw who had some success in A ball this year, earning his first bump to Double-A. He’ll throw a sinker, a cutter, a slider and a changeup with some interesting pitch shape, but is working to add velocity (88-89 mph on the fastball).

Ben Ethridge, RHP: Taken in Round 15 of the 2022 Draft out of Southern Miss, Ethridge spent his first full season as a swingman type for Single-A Fort Myers. He has a four-pitch mix with a four-seamer, a slider, a curve and a changeup, and his main focus is adding velocity to a fastball that sits at 90 mph.

A.J. Labas, RHP: A nondrafted free agent signed out of LSU, Labas has an east-west profile, with a sinker that has good depth, a cutter and a sweeper. He’s shown some ability to miss bats but is working on refining his command.

Zach Veen, LHP: Veen was a late-round pick in 2022 and spent his first full season pitching out of the Fort Myers bullpen. He might profile best as a sinker-slider reliever type (he does have a cutter and changeup) but he needs to add some velo to his 88-89 mph fastball, something he’s focusing on this fall.