The largest immediate improvement needed is in the pitching staff, so omitting any pitcher would be gross negligence. There are several pitchers the Royals should move on from. Frankly, most feel unrealistic. Reasons range from financial to the ability to notably improve, or a combination of the two. But the one player Kansas City could designate for assignment and retain feels like Max Castillo.
Castillo, along with Samad Taylor, came to Kansas City in the Whit Merrifield trade. Castillo made his Royals debut first between the two, pitching in five games in 2022. His appearances resulted in a 9.16 ERA and 1.768 WHIP, but the poor performance was forgivable as Castillo was green. How a year changes things.
Castillo appeared in seven MLB games, sprinkled across May, July, and August. He served only as a multi-inning reliever, averaging nearly three innings per appearance. His performance was all over the place, but he allowed at least one run in five of his seven starts. Whether serving as the bulk man or relieving a starter exiting early, Castillo was far from dominant. He ended the season with a 4.43 ERA and 5.32 Fielding Independent Pitching (FIP). A lack of strikeouts and a normal walk rate ballooned his FIP as he relied on pitching to contact.
I understand that Castillo is still young and controllable. The fact is, he does nothing remarkable at the MLB level, and his extended results at Triple-A Omaha offer little hope. Castillo ended this season with a -.1 fWAR, appropriate for what he brought to the MLB staff. The changeup and slider have some promise, but he has not done anything special so far. Trading Castillo is not the ultimate goal. Replacing him with a free-agent signing is.