KC Royals Prospect Q&A: John McMillon talks MLB debut, offseason progress

The reliever made his MLB debut late in the 2023 season.
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There is likely no bigger pitching development success story in the KC Royals system than reliever John McMillon. The righty reliever began the 2023 season in Low-A Columbia and ended up pitching in the majors before August's end. Sure, the 25-year-old was more polished than his lower-level competition, but the ease he made each transition was impressive.

KC Royals fans only got a taste of John McMillon at the MLB level last season.

McMillon also made the jump from Double-A Northwest Arkansas to the MLB club. The Texas Tech alum made his debut on August 17 against the Seattle Mariners. He gained his first blemish by surrendering a solo home run, but that was quickly forgotten.

He struck out eight batters over four innings, with that home run being the only hit and run he allowed that season. McMillon's season ended early sadly with some forearm tightness, but big things are expected of him in the 2024 season.

Kings of Kauffman co-site expert Jacob Milham caught up with McMillon as he prepares for spring training, which is quickly approaching.

KOK: How were the holidays for you?

JM: It was good. It's always, yeah, nice to be able to spend some time with family. And get the whole holiday experience. We have a big family Christmas. And every New Year's, we get together and we all eat black-eyed peas and cabbage for health and wealth.

KOK: January is in full swing; we're about a week into the New Year. But are you back in the full swing of things? Are you still taking a rest?

JM: It's pretty much full-go at this point, you know, with training, building up a throwing program, making sure everything's tuned up right, and getting ready to roll for the season. You know, it's a long season, and it's pretty important to utilize your time as best you can to make sure your body is ready to go out there and perform at the level you want. Every year, I feel like you're working hard in the fall, right after the season. You never really stop, you know. But when the middle of December comes—Christmas time, you know—you start thinking about February. It is always sooner than you think.

KOK: Wow, that sounds like if you try and get some significant downtime, you are behind the ball right away.

JM: Sometimes, yeah. You know, everyone's body's going to be different. Everyone responds to training and stimulus differently. But I've always found that the more active I am, the more I do, the better things seem to go.

KOK: Glad to hear. Listen, other than building that back up and just staying in playing shape, is there anything else you're trying to work on or work through this off-season?

JM: I'm not really a fan of the term mechanical adjustment. But there is one thing that I was working on last year: just trying to stay really in line with the target. So I'm a north-south pitcher. So I want all my misses to be up or down, not left or right. So I'm just emphasizing that carryover from last year. And making sure I'm staying in the lane—it's like a kind of mental cue of your path towards the target.

KOK: You made some headlines last year, starting in Low-A Columbia and eventually making your MLB debut the same year. What was making your MLB debut like?

JM: You know, it was very exciting. It's almost like Christmas morning. You know it is coming, and you've anticipated it your whole life. But it is pretty surreal whenever you get that phone call. Like, "Hey buddy, you've got a trip to make!".

KOK: Now, moving on to your MLB debut. Unfortunately, your second batter up gave up a home run. In retrospect, it isn't that bad, but in that moment, how were you feeling?

JM: I was wondering if he knocked down the foul pole, honestly. When you throw it hard, if they get a barrel on it, every now and then they get one. At that moment, I was okay with moving on to the next pitch. Just stay pitch to pitch, executing the next pitch. I thought it wasn't a bad pitch he hit; he just made a good swing.

KOK: It sounds like a good gameday mindset. Your MLB time was short, but what were some positives on and off the field looking back?

JM: Man, the stadiums you get to play in. The competitive environment is pretty fun. It is just a lot of fun. You get to see all the guys competing every day, not knowing if you're going to pitch that day or not. I just feel like we have great coaches; everyone is trying to put us in a position to compete and win. I mean, it is just fun, man.

KOK: There are worse ways to make a living. So, this is going to be your first MLB spring training. How are you feeling ahead of the report date?

JM: I feel pretty good. I'm a little heavier than I was at the end of last season, and that's normally what happens again. Typically, I lose weight during the season. But you know, once I get to that good middle ground between where I want to be physically, I'm going to be able to do that. And mobility-wise, for throwing, I'll hang out right there. I'm feeling good. I've been on a really good training program. And I feel like I'm moving fairly well. I'm really looking forward to it.

KOK: Just curious: what does your throwing program look like? Just what the team tells you, or do you look for third-party help?

JM: I got a new training facility this offseason. In the years previous, I did a mix of things that I got from the Royals training and some stuff I did in college that I liked and that I think helped me get prepared to go throw. I got this facility out here in Fort Worth called APEC, and yeah, it's good; it's just a really good community. And they're a good training program.

KOK: Hey, as long as you are feeling good, that is what matters. Let's move away from baseball for a second. Do you have any hobbies or interests you're passionate about outside of baseball?

JM: I like to hunt, and I mean, I cook a lot. I don't know if it's a passion of mine. It feels like a chore sometimes, but I mean, I'm pretty passionate about health and fitness, and I play the guitar. It's a little hobby I do that's really good during the season, whenever you get back from the ballpark.

KOK: Wrapping up, do you have any goals for the upcoming season?

JM: I do. But you know, man, right now I'm just really focused on being the best pitcher I can be. And help. Just try to help the team as much as I can. And you know, the rest of the chips will fall where they may.

KOK: It's not a bad way to live. So, I asked Javier Vaz this question and want to ask you. What are some lessons you have learned on the mound and in the dugout?

JM: Oh my gosh. Man, that's a loaded question. It's almost indescribable, but, to me, it's always been cool to watch other guys compete because you feel it yourself, but you can't ever see yourself do it. When guys are competing to their full, highest capacity, and whenever they're stepping it up and performing. That's always been something really exciting for me to see. To put the nail in the coffin. It's like a thing we used to say in college a lot. You build a little momentum, and guys just go into attack mode. You can learn a lot from watching other guys compete, and what greater lesson do we need than to compete? Not just in baseball, you need to compete in life, and there is a lot of value in being a good competitor.