Back in the early days of Spring Training this year, when Royals officials and staffers discussed the Minor League players who were about to arrive for camp, the organization’s most recent Draft picks were discussed more than the rest. The 2021 season would allow what the 2020 canceled Minor League season did not: the first real look at these players competing in a Royals uniform.

One of the more intriguing players in that group was right-hander Will Klein, a fireball reliever with a devastating changeup -- and a potential to start. And what he showed in that first look made the Royals all the more excited about what’s to come.

After a successful 2021 campaign, Klein was named the Royals’ Pitching Prospect of the Year by MLB Pipeline.

“When I learned that I could trust my stuff a lot more than I thought, that changed things for me,” Klein said in a recent phone call with MLB.com. “I was a little nervous to start the season. Who wouldn’t be? But we’re drafted for a reason, and I think I got more aggressive and more confident as the season went on.”

Klein was effective as a multi-inning reliever in High-A Quad Cities, posting a 3.20 ERA in 70 1/3 innings with 121 strikeouts. Often throwing higher leverage innings for the Bandits, especially during their High-A Central Championship run, Klein had a 1.24 WHIP and held opponents to a .173 average.

He worked off a specific plan laid out by the Royals' development staff at the beginning of the season to make sure he got his innings in while also being cautious with his workload coming off the low-inning 2020 season. Klein routinely threw around two innings (roughly, based on pitch count) with a bullpen session in between to work on his secondary pitches.

“That went really well,” director of pitching performance Paul Gibson said. “We built a plan, and he’s one of the guys that stayed healthy from front to end and developed immensely. We couldn’t be happier with his development this year.”

After a rough July, with a 4.41 ERA in 16 1/3 innings, Klein worked with pitching coach Steve Luebber to make some mechanical changes in his delivery -- mainly staying back and not rushing through the motions -- and posted a 1.29 ERA over 14 innings in August.

“I had a crappy few outings in July, and was like, ‘I can’t let that happen again. That’s not who I am,’” Klein said. “So that kind of flipped the switch. Those mechanical changes helped to make it more feasible to where I could maintain my confidence and back it up a little bit. The whole month of August kind of reinforced what I was about.”

Klein, who was drafted in the fifth (and final) round out of Eastern Illinois University in 2020, lives on his fastball. He touches 100 mph with it regularly as a reliever, something he first did during his breakout summer in the Northwoods League in 2019, where he finished with a 0.86 ERA and 38 strikeouts in 21 innings in the wood-bat circuit. He has a crushing curveball, and he relied on those two pitches the most this season in the later innings he pitched.

The pitch that gives Klein the most intrigue, though, is his changeup. He made significant strides with it this year, especially in those side sessions, and recently began throwing with a more natural grip, which he likens to what’s colloquially nicknamed as the “fosh” changeup. It’s a rare grip, and each pitcher who throws it employs his own variation in terms of grip. But it’s somewhere between a splitter and the more typical changeup.

One of the questions Klein faced when he was drafted was about his changeup and his inability to take velocity off it. With this new grip, he keeps the same arm speed and angle -- while taking significant velocity off the changeup.

“The old circle changeup, it was like 92-94 mph, so it had some separation, but it wasn’t enough for the movement. It was basically a crappy two-seamer,” Klein said. “It wasn’t really what I wanted for a changeup. The new one I’ve been throwing, I’ve liked it a lot more, but threw it sparingly because we were in playoff mode. But it was anywhere from 88-90 mph. I was really happy with the results.”

Improving his changeup is his main focus for the offseason. The Royals believe Klein’s changeup could give him the ability to start, although they recognize that he’s going to get to the upper levels quicker -- and help the big league club sooner -- if he stays as a reliever.

“I think we’re leaving all the options out there right now,” Gibson said. “Starting pitching is hard to come by and we’re in the business of developing starting pitchers predominantly. I don’t think any of us want to close that door, but we’re also mindful of what his abilities are out of the bullpen as well.”