SURPRISE, Ariz. -- Alec Marsh had never felt adrenaline like he had pitching on the mound in big league camp this year.

First it was the right-hander’s first live batting practice, facing just a few of the Royals regulars -- Andrew Benintendi, Michael A. Taylor, Adalberto Mondesi and Carlos Santana. Then it was his first Cactus League appearance on March 7, when he pitched a scoreless inning with one strikeout against the Padres.

“My first live [BP] here, that first big league appearance -- I’ve never experienced that before,” Marsh said. “Which is awesome because I need to. The live was more [intense] than in-game, which I thought was surprising. I was pretty amped up. It was hard to breathe that day.”

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What Marsh showed in those two times on the mound in big league camp only solidified how the Royals view one of the fastest-rising pitching prospects in their system.

“I didn’t really know much about Alec up until we got to that fall camp in K.C. last year,” Royals manager Mike Matheny said. “He was one of the highlights I took out of that time I got to spend with those guys. A lot about stuff, which he was able to display, but even just as much about the makeup, the heart, the competitor. He’s strong as an ox.”

Marsh, 22, had one of the Royals’ biggest jumps in MLB Pipeline’s Top 30 Royals Prospects list this season, which was released Tuesday. After landing No. 24 on the 2020 list, Marsh is up to No. 12 -- a testament to the strides he made despite playing no Minor League games last season.

About a month into baseball’s shutdown last year due to the coronavirus pandemic, Marsh drove from where he was staying in California back to Tempe, Ariz., to work out at a gym called Push Performance, where other Major League players were training during the break. Marsh worked on strength, mobility and explosiveness in his workouts, but most importantly, he was in an environment with big league players.

“Just being around their mindset, seeing them work, was awesome,” Marsh said.

Marsh trained there until he was itching to get back on a mound. He found an independent league team in Sugar Land, Texas, and asked the Royals if he could pitch there. They cleared him to pitch for Eastern Reyes del Tigre, whose pitching coach was Dave Eiland -- the Royals’ pitching coach from 2011-17.

Marsh was on a pitch count and only pitched a few innings, but Eiland was impressed with what he saw and told the Royals so. The organization brought Marsh to their alternate training site in September and kept him in Kansas City for their fall camp.

When Marsh pitched for them, the Royals were looking at a different pitcher than the one they selected in the Competitive Balance Round (No. 70 overall) in the 2019 MLB Draft. His velocity had jumped. His breaking balls were sharper. His competitiveness stood out, as did his physicality after his training at Push Performance.

“You look at him, and that’s the kind of guy -- that body type, that pitch type -- who could be around the game a long time,” Matheny said. “It’s nice to see him get out there and throw his name in the mix with everybody else. I think that’s what he wants: ‘Just put me in with the rest, let me go out there and fight for this, show you what I can do.’ It’s just another name to add to a really exciting young list of guys.”

When Marsh was drafted, he made it a point to tell the Royals he wanted to be included in the loaded group of pitchers they drafted in 2018 -- Brady Singer, Kris Bubic, Daniel Lynch, Jackson Kowar and more. He watched them pitch in person for the first time in '20 and walked away impressed.

“Who wouldn’t want to be in that conversation?” Marsh said. “Those guys are really good. I don’t think I’m far off at all, but I think it’s just playing baseball. I want to put myself in a room where I’m the worst guy because it’s only going to make me want to get to the top and then find another room. That’s how I view things.”

Over the past year and a half, the Royals have watched him go from saying he wanted to be in that group to showing that he can be.

Marsh possess a power fastball that flashes 98 mph, with his goal of hitting 100 mph not far off. It has late cut to it, and he complements it with a two-seamer that has good sink. He possesses two distinct breaking balls: a tight slider that he can throw for a strike or bury outside the zone and a looping curveball. His changeup was his biggest focus over the past year after watching Kowar use the pitch at the alternate site and fall camp last year. Marsh’s has the potential to be above average and will play well off his fastball with a different look.

“I think that’s my best pitch right now,” Marsh said of the changeup. “I think it’s the pitch that’s going to be really good this year, especially if my velo’s that high, it’s going to be hard to hit. Keep guys off balance, throwing it 86-87 mph. And it moves. It’s just one other pitch for guys to worry about.”

Marsh was reassigned to Minor League camp last week, and he’ll likely start the season in the Double-A rotation. But as the last year has shown, he’s one to keep an eye on in a farm system loaded with pitchers.

“I feel like that power pitcher that I’ve always wanted to be,” Marsh said. “I don’t think it’s even close to my maximum potential yet either, which is awesome.”