Prospect Profile: Will Klein

Will Klein should be a familiar name among Royals fans. He was the team’s lone representative at the 2023 Futures Game. Klein was also the organization’s Pitching Prospect of the Year in 2021, according to MLB Pipeline. He’s a flamethrowing reliever with a dominant fastball, a good curveball, and excellent strikeout ability. The walks have limited him at times in the minor leagues, but when he’s been able to command his arsenal, the results have been fantastic. Klein reached the minors’ highest level after the Futures Game last season, and as an offseason addition to the 40-man roster, he’s knocking on the door of the big leagues.

Season Stats:
2021 (High-A): 36 G, 70.1 IP, 3.20 ERA, 2.99 FIP, 40.9% K%, 14.9% BB%
2022 (AA): 30 G, 43.2 IP, 10.51 ERA, 6.60 FIP, 23.7% K%, 22.0% BB%
2023 (AA): 21 G, 29.1 IP, 3.38 ERA, 2.77 FIP, 33.6% K%, 10.7% BB%
2023 (AAA): 28 G, 35.0 IP, 5.66 ERA, 4.37 FIP, 28.2% K%, 14.4% BB%

Klein will almost certainly pitch some innings in Kansas City this upcoming season. His command has been up and down throughout his time in the minors and he’s never quite reached the same strikeout rate that he accomplished in his stellar 2021 season. With that said, he’s also pitching against more advanced talent in the minor leagues as he’s progressed. His arsenal includes a four-seam fastball, a cutter, and a curveball. The curveball is closer to average but plays very well off his heater and that amplifies its effectiveness.

His four-seamer sits in the upper 90s with ease. At times last season, we saw Klein work backward when he needed to and it worked well to keep hitters off balance. His stuff would play in the big leagues right now and there’s a chance he will break Spring Training with the Royals. As long as he continues with a strikeout rate of around 30%, as we’ve seen most of the time with Klein, he can still succeed with the amount of walks he’s usually allowed. He ranks somewhat low here, at 36 but not because he lacks talent. That’s more reflective of the relievers in general and the inherent volatility of the position.

Scouting Grades:
Fastball: 70/70
Curveball: 50/55
Command: 40/45

Best Case Scenario

There’s a reason Klein was named the organization’s pitcher of the year in 2021. When he’s on, there aren’t many better relief options in the system. We saw the success that John McMillon had last season in a limited sample. Klein could find similar success given the chance. It wouldn’t be surprising at all to see Klein and McMillon form a formidable one-two punch in the backend of the Royals bullpen as early as mid-season 2024. Corey Knebel was a dominant strikeout arm for some time in the big leagues and Klein could be a very similar arm.

Worst Case Scenario

Klein will almost certainly pitch in the big leagues in 2024. What’s left to see is whether he will pan out as a mainstay in the bullpen for years to come, or if he will struggle and revert to organizational depth. No matter what, regular triple-digits out of the bullpen will play in the big leagues. Even the worst case with Klein likely involves some big-league innings, albeit maybe as a middle-inning reliever instead of a lockdown setup man in the back of the bullpen.

Preston Farr

I cover the Royals and their minor league system for both Farm to Fountains and Royals Review. I also cover prospects throughout the minor leagues for Prospects Live.

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