CHARLESTON, WV – The Pirates have sent some high upside pitchers to West Virginia over the last several years. They had Jameson Taillon making his debut at the level in 2011, one year after taking him second overall in the MLB draft. Taillon had top of the rotation upside from the day he was drafted, so you knew he was a top prospect coming in.
Then there was Tyler Glasnow in 2013. He was a bit more raw and under the radar, hitting 96 MPH the year before and putting up some impressive numbers in rookie ball, but not quite having top of the rotation potential before his arrival. He broke out that year, and that led to him being viewed as a future top of the rotation starter.
And now they have Mitch Keller.
I’ve been hesitant to group Keller in with those other two starters, just because it’s unfair to put that kind of label on a young pitcher in the lower levels too early. Keller didn’t really have a ceiling when I saw him in the GCL in 2014, and had the makings of a plus fastball and a plus curveball. A future at the top of a Major League rotation was possible, but the risk was way too high to say it then.
After seeing Keller again this week — for the second time this season in West Virginia, after multiple times in Spring Training — I’m comfortable comparing him to Taillon and Glasnow. And that’s mostly because I can’t think of a reason not to make the comparison. In fact, Keller might even be ahead of where Glasnow and Taillon were at this same level. Let’s break down why.
The Fastball
Keller absolutely dominated in his start on Friday night, pitching five shutout innings, with four hits, one walk, and seven strikeouts. It was the second start in a row where he shut down Delmarva, following a start where he threw six shutout innings with no walks and nine strikeouts. That’s only one team, but the stuff Keller was showing is something that can be effective against any team.
The biggest thing that stands out is his velocity has jumped this year, sitting 94-97 MPH in the start. He’s actually been sitting there for the last few outings. When I saw him in April, he was sitting 92-95 MPH, which was an uptick from when I saw him last year. In his final inning on Friday, he was sitting 93-95, and hit 96 and 97 once each. When I saw him in April, he dropped in velocity the final few innings, sitting around 92-93. Keller has increased his velocity in every way, and is holding that velocity throughout the start.
“It’s pretty cool to see that, all the hard work I’ve done in between starts. I’ve definitely been working hard and leading to that,” Keller said, while also noting that it still feels like he’s throwing 89-90. “Just getting stronger in the weight room. Delivery stuff, the front arm. Just taking a lot of unneeded energy out of my delivery, and putting it towards the pitch.”
I’ve written about Keller’s change to his delivery coming into the year. He is now holding his glove arm firm and above his waist during his delivery, rather than letting it drop down and swing out to the plate. That took a delivery that had a lot of moving parts, and made it simple, as you can see in the video below from Friday’s start.
https://www.youtube.com/watch?v=E4JcX_lP0yA
“I think I nailed that,” Keller said of the delivery adjustment. “Now I’ve just been moving on to more stuff, trying to get my delivery better, and adding some velo too. That’s really helped out too. I’ve seen an uptick on the velocity the last two or three outings. It’s all coming together, especially with that glove arm, it’s really helping me to control where I want to throw the ball.”
The Pirates put young players through strength building programs, which has helped Keller to get stronger as the season has continued. But the simple delivery has played a big role in his velocity increase this year.
“I’d say that’s the main contributor for it,” Keller said. “Having that, and being strong and stable has allowed me less moving parts in my delivery, to keep everything in line.”
But the velocity is only part of what makes Keller’s fastball so special right now. He also gets good downward movement on the pitch, and is getting to the point where he can dominate the South Atlantic League using only his fastball. In his start on August 6th, when he pitched six shutout innings and struck out nine, he didn’t throw an off-speed pitch until the fourth inning. He could have continued that approach, but the coaches wanted him working on his secondary stuff, just to make sure he was getting his work in.
“They were so late on it, there was no need to throw anything else,” Keller said of his fastball that night.
This continued in his start on Friday. He threw two curveballs in the first inning, one curve in the second, and two changeups in the third. He increased the usage of his secondary stuff later in the outing, throwing seven off-speed pitches in the fifth, which was more than he threw in those first three innings combined.
West Virginia Manager Brian Esposito is less focused on the velocity of the fastball, and more focused on the effectiveness of the pitch, which has definitely been working for Keller.
“Velocity really in my opinion isn’t everything,” Esposito said. “It’s more the quality of the fastball. Is he throwing it downhill, is he getting swings and misses, or is it producing a lot of foul balls? If it’s big velocity and we’re not getting anything off the pitch, and it’s a foul ball, or balls that are put in play kind of hard, velocity doesn’t make any difference to me. As long as he’s pounding the ball down with that velocity, now we’re talking about a different animal now.”
Keller shared some feedback he got from his pitching coach Matt Ford on how the fastball has changed throughout the year with the added velocity.
“It’s getting a lot more run and sink to it, and that’s really good for just a four-seam fastball that it’s getting that kind of movement on it,” Keller said.
This is the first big separator between Keller and the top of the rotation guys who came before him. Taillon and Glasnow also sat mid-90s in West Virginia, but their fastballs weren’t as effective. Taillon’s was flat and up in the zone, making it very hittable. Glasnow had a ton of movement, but also some horrible control, which meant he wasn’t getting hit, but was hurting himself at times.
Taillon obviously fixed his problems over the years, and Glasnow has made some strides, but still has room for improvement. Meanwhile, Keller is ahead of where both of them were with their fastballs at this level. He’s showing velocity, movement, and command of the pitch, and each time I see it, it continues to get better. That’s not to say he will have the best fastball long-term. But there’s much less to develop here than there was with Taillon and Glasnow.
The Off-Speed
One big appeal for Glasnow and Taillon was that they each had great curveballs. They were both plus offerings, which combined with the velocity of the fastballs, gave the potential for two plus pitches. Keller has the same thing going for him. It’s not always consistent, but that was never the case for Taillon and Glasnow, and consistent command of the pitch is something that will come over time.
The changeup is another big separator here. Taillon had so much focus on his mechanics and getting some downward movement on his fastball that he didn’t start really pushing the changeup development until the following year in Bradenton. Glasnow was so focused on control in the lower levels that the changeup was more of a secondary concern. He also has never really trusted using it, which hurts the development.
Keller has had less work to do with his fastball this year, which has allowed him to put a big focus on the changeup. It helps that Keller knows the importance of that pitch.
“He knows to be a Major League pitcher, you need a changeup,” Pitching Coach Matt Ford said. “That’s something we were nailing in our bullpens. He was nailing in his throwing program and flat ground work. Really worked on it, and as the season progressed he got a lot more confidence with it. He found spots to throw it, especially to lefties. But it’s just part of the whole package now, which is great to see.”
Early in the season, Keller was focusing on using the changeup just to get more comfortable with the pitch and to develop the pitch further. He’s now to the point where he is starting to use it in situations where you’d use a changeup, rather than just throwing it to develop the pitch. For example, on Friday he threw it in a 1-0 count with a runner on to get a double play. Keller said those types of results give him more confidence in the pitch.
“His changeup has improved leaps and bounds,” Esposito said. “He’s graduated from just throwing it, because he needs to use it, he needs to develop it, to knowing that this is a weapon for me, and this is the equalizer of my fastball. Guys want to hunt my fastball, I’m going to be able to pull the string and I’m going to get you to roll some things over. He knows how to use it now. Not only is it a good pitch for him, but it becomes a weapon for him, which is awesome.”
The changeup could still use some improvements. He was mostly around 89-90 MPH in the few pitches he threw on Friday, and you’d like to see that go down to provide more separation from the fastball. But the pitch does have some good movement, giving him a good foundation to work from going forward.
“Those will get sharper as time goes on,” Ford said of his secondary stuff. “I think it’s more knowing how to use his weapons, when to use his weapons. We do a lot of video review and stuff like that. Reading hitters, hitter ID, foul ball ID. He’s starting to get a real good feel with that, and he knows that’s something he’s going to have to own going forward.”
As for the comparison to Glasnow and Taillon, this is no contest. Keller actually has a changeup at this level, while the other two were working on their fastballs. Again, that doesn’t mean he will have a better changeup in the long-term. Taillon has a good one now, although Glasnow still doesn’t have one. The fact that Keller has laid some solid groundwork on the pitch gives him a good shot of having a good changeup in the future.
Still Things to Work On
Keller’s season has been outstanding. He has a 2.72 ERA in 112.1 innings, with a 9.5 K/9 and a 1.2 BB/9. He said that he’s still feeling good, and not feeling fatigued, despite more than doubling his career innings total from the previous two seasons combined. He actually has one more inning than Glasnow had at the level, and is well beyond Taillon’s count when the Pirates were very restrictive of the workload in 2011.
The focus now is less on innings, and more on pitches and stress pitches. As you’d expect, Keller hasn’t had many stress pitches this year. He’s reviewed by Ford, Esposito, and the performance staff after each start, with his recovery between starts being the key focus. So far, it doesn’t look like he’s losing anything or getting fatigued later in the year.
“It didn’t look like it tonight,” Ford said with a laugh after Friday’s start.
There was a stretch recently where Keller did struggle. He had a 4.47 ERA from the start of June through his first start in August. He also only struck out 39 batters in 44.1 innings. The slump was mostly due to his mechanics, although a fix has been identified.
“I was leaving the ball up in the zone, and got more hits, more balls getting through the holes, unlucky breaks here and there,” Keller said. “I just wasn’t staying back in my delivery. Trying to find out what was leading to that, and I think we found what the problem was. So I think just moving forward, kind of nailing what we identified, that will help.”
Keller has fixed the issue, keeping his weight on his back leg longer, using his legs more to generate power and downward movement on his pitch. This has also contributed to the added velocity lately. Esposito actually felt the rough stretch was good for Keller, as it forced him to work on cleaning up a few things.
“Everybody needs a good beating every now and then in my opinion,” Esposito said. “It keeps you humble, and it keeps you sharp to work on the things you need to work on to advance.”
Keller looked good mechanically on Friday, and didn’t seem to have any issues. We’ll see if that continues in his next start against a team that isn’t Delmarva, but with the way he’s pitching, I don’t think the team matters right now.
“He’s a guy who is starting to own a delivery,” Ford said. “He’s getting comfortable with it, and he’s using his lower half properly now. I think that’s what you’re seeing.”
A Future Top of the Rotation Starter
After seeing Keller’s latest start, and seeing the continued improvements he made, I was asking myself questions like “Does Mitch Keller belong in the top prospect tier with Glasnow, Austin Meadows, and Josh Bell?” and more extreme questions like “Could Keller actually be the top prospect in the system right now?”
Think about it. Taillon and Glasnow were both highly rated prospects after their time in West Virginia. Taillon rated second in the system, only behind Gerrit Cole. Glasnow was third, behind Gregory Polanco and Taillon. Keller is ahead of both of them in many ways at this stage. There is the disclaimer that Keller is older, although the difference is small. He’s four months older than Glasnow was at this level, and seven months older than Taillon was at this level.
Keller has the same velocity they had at this level. He has a much better fastball, with more deception than Taillon, and much better control than Glasnow. In fact, his fastball might be the perfect combination of the fastballs Taillon and Glasnow had at the level. All three had plus curveballs. And Keller is way ahead of the other two in terms of his changeup development.
At this point, I definitely think Keller has jumped up into that top tier, and I don’t think it’s crazy to suggest he’s a strong contender to be the top prospect in the system. The prospect rankings reflect long-term upside. I see his upside as a top of the rotation starter. I see the same thing with Glasnow, but the crazy thing is that Keller might have the same amount of risk, or possibly less risk, due to his better fastball command and changeup. Austin Meadows and Josh Bell are also in that tier, but I think Keller’s value would be higher than Bell’s due to the defensive downside from Bell. Meadows would give him some strong competition.
As I always say with tiered rankings, the rankings within the tiers are just a matter of personal preference. There’s really not much separating those guys, and you could argue any of them as the best prospect in the system for various reasons. I think the most important thing is that Keller looks like a guy who belongs in this tier, with Glasnow, Meadows, and Bell. And one day, he looks like a guy who will fit in at the top of the rotation in Pittsburgh with Taillon and Glasnow.
