SURPRISE, Ariz. -- The Royals added several pieces to a revamped bullpen this past offseason, bolstering the back end with a quartet of high-leverage veteran arms while maintaining a promising group of depth options.

One such depth reliever won't be breaking camp with Kansas City -- but don't count out intriguing homegrown prospect Will Klein from catching on with the big league club at some point this season.

Klein, the Royals' No. 19 prospect in MLB Pipeline's updated rankings for 2024, was optioned to Triple-A Omaha following Friday's 4-2 win against the Rangers at Surprise Stadium, but he has impressed with both his demeanor and his stuff in his first big league camp.

Added to the 40-man roster last November in order to protect him from the Rule 5 Draft, the 24-year-old Klein has risen through Kansas City's farm system since he was selected in the fifth round of the abridged 2020 MLB Draft.

He earned a selection to last year's All-Star Futures Game in Seattle and will have the chance to perform on another big stage in the inaugural Spring Breakout on March 17.

"It's an honor," Klein said. "I'm honestly tired of being a prospect at this point, though. It just means you haven't done anything yet. I'm ready to actually help the team win."

His days as a prospect could be numbered if he continues to throw the ball the way he has so far in camp.

With the disclaimer that spring statistics do not necessarily translate to regular-season success, Klein has yet to allow a run in four Cactus League appearances, recording six strikeouts against two walks in 3 2/3 innings.

Klein had been scheduled to pitch against the Rockies at Salt River Fields on Thursday, but he instead threw a simulated inning after the game was rained out, as the Royals opted to stick with their pitching plans in Friday afternoon's game against the Rangers rather than push everyone back a day.

“He’s a perfect bullpen piece," pitching coach Brian Sweeney said recently. "He’s got that late-inning reliever mentality. He’s got the beard. … You sense a quiet confidence about him. An arrogance in a good way that a reliever needs when he comes in in tough situations."

Klein's 6-foot-5 frame and power fastball give him an imposing presence on the mound, but that confidence has steadily developed with time. He's not shying away from attacking the zone this spring, which he attributes in part to a change in mindset.

"I wasn't really scared last year, it was just a little more like, 'Oh, they're really good hitters, you gotta paint corners,' stuff like that," Klein said. "It's like, 'They're still really good hitters, but I'm a better pitcher. I'm just gonna go beat 'em in the zone.' That's a huge thing that I worked on, that kind of meshing of process and results there."

Klein split 2023 between Double-A and Triple-A. He posted a 3.38 ERA in 21 appearances for Northwest Arkansas before a midseason promotion to Omaha, where he notched a 5.66 ERA in 28 games. The Royals' right-hander said he struggled to throw his curveball for strikes once he reached Triple-A and has placed an emphasis on making that adjustment this spring.

"When you've got good hitters that can eliminate two pitches that aren't in the zone and just attack fastballs, it's hard to pitch," Klein said. "Making them work on seeing three pitches versus, like, one and a half, two, is huge."

So far this spring, Klein has been able to drop his curveball in the zone, setting up his fastball nicely.

“He’s got that power fastball. How are we going to complement that? Is it going to be the curveball or slider? I think it would be awesome if he could have both," Sweeney said. "If he can lay one in there for a strike, the other for a wipeout pitch. All of a sudden you’ve got 97-98 mph at the top of the zone that you’re swinging through.

"What’s really important to his career is how can he fill up the strike zone with those offspeed pitches so he can get hitters off his fastball?”

The real test for Klein will come once spring is in the rearview mirror and the regular-season Minor League schedule is in full swing. But if he's able to keep up his offspeed command, his path to Kansas City becomes that much more clear.