When it comes to rookies making their pro debuts, I view their performances on a different scale than I would an established MLB player. Expecting a prospect to come up and dominate in his first run through the majors is a bad approach, even if that prospect is expected to dominate in the future. What I look for in a pro debut is how a guy’s stuff plays, and whether he actually looks the part.
Chad Kuhl looked ready, despite poor stats that led to three earned runs on four hits and four walks in five innings. Steven Brault looked ready, despite only going four innings. Jameson Taillon gave up three runs in six innings, with two walks and three strikeouts, but he also looked ready.
As for Tyler Glasnow, the version we saw today was a guy who looked ready for the big leagues. At the same time, Glasnow still has a lot to work on.
I’ve been talking about Glasnow all season, and saying the same thing for why he doesn’t look ready. He’s a guy who has a plus fastball with on and off control, along with a plus curveball that is devastating when he’s ahead in the count. He also doesn’t really trust his changeup, and needs to use it more to improve the pitch. For the most part, that’s what we saw in his debut. But there was one key difference today.
Due to the lack of a changeup, Glasnow has really only had one pitch to use early in the count: his fastball. He hasn’t been the best at commanding the pitch around the edges, leading to a high walk total when he gets a bit wild. We saw that today, not just in the first plate appearance when he issued a seven pitch walk with all fastballs, but at various other times when he fell behind early in the count on the fastball.
In that situation, with no changeup, Glasnow needs to use the curveball as a strike pitch to get back in the count. For the most part, he did a great job of that today. He threw a few first pitch curveballs for strikes, and a few curves for strikes when he was behind in the count, helping to battle back. That’s something he hasn’t always done a good job of this year in the minors, and the reason is that the curveball isn’t always consistent in that scenario. Unfortunately, we also saw that today.
To illustrate this point, here is what the curveball should look like when he’s using it for early strikes, or to battle back in the count.
That was a 2-0 pitch where Glasnow dropped the pitch right in the middle of the zone for a strike. There were a few other times where Glasnow was in the middle, and it didn’t work for him. The key with this pitch is the movement. The curve comes in right-to-left, then has late bite that drops down into the zone.
The problem is that Glasnow doesn’t always see this same movement. Here was a first pitch curveball to Randal Grichuk in the fifth inning with one out, and it was taken for a solo homer.
The pitch is in the middle of the zone, and a bit to the right, but you can see the movement isn’t the same. The pitch doesn’t travel as far right-to-left, and definitely doesn’t have the same late bite. The result is a curveball that barely moves, and is flat in the middle of the zone. It’s no surprise that pitch ended up a homer.
The curveball is fine when Glasnow is ahead in the count. And “fine” might be an understatement. The curveball is just filthy when Glasnow is ahead in the count. Ask Stephen Piscotty about that.
Glasnow just lets the pitch rip, burying it in the bottom of the zone. If it travels out of the zone, it’s fine, since Piscotty is in a position to commit early on the pitch. It’s got so much movement that when he sees the pitch at first, it’s over the middle. By the time he has committed to a swing, it’s already in the bottom corner of the other side of the strike zone.
That was a 3-2 pitch, and a bit daring for Glasnow to go to it in that case. But here is another example where Glasnow used a 1-2 curveball against Yadier Molina, giving him nothing to work with.
In this case, Molina is in position to protect anything that looks close. Once again, the pitch comes in looking to be at the bottom of the zone, and near the middle. By the time he’s swinging, it’s low and away, and all he can do is make weak contact for an easy pop up.
As far as hitting a spot, that isn’t a good pitch. But when you’re in that count, you’re not looking for hitting a spot as much as you’re looking for the movement on the pitch, and getting the opposing hitter to commit early and chase. If you mess up here, the worst that usually happens is they lay off the pitch and it goes for a ball.
With the early curveball, it’s absolutely about hitting your spot. There is little room for error. When you mess up on that pitch, the ball can travel a long way, as we saw above.
As I wrote today in The Book on Tyler Glasnow, there has been a long history of articles we’ve written where Glasnow discusses adjusting his changeup, only for game reports to say that he either rarely threw the pitch, or was forced to use it. At the MLB level, you can’t force a guy to use a pitch for development purposes. It’s all about winning. So if Glasnow stays up, it’s unlikely he’s going to be using the changeup that much.
This makes it so important for him to use and command that early curveball, dropping the pitch in for strikes. If he can do that consistently, then he can make up for any fastball control issues he has, while also avoiding opposing hitters sitting on the fastball early in counts, or when they’re ahead.
What I liked today was that he showed the tendency to use that pitch in those situations, and had a lot of successful pitches in the process. But as we saw with the home run, and with a few other curveballs that weren’t executed, he doesn’t always command that version of the curveball. Triple-A hitters weren’t capitalizing on those mistakes, but MLB hitters will make him pay. If Glasnow is going to stay in the majors, and continue not trusting his changeup, then he’s going to need to master the command of that early count or behind in the count curveball.
**I wouldn’t be surprised to see Glasnow get sent down tomorrow, and that would be the right call. He could go down, pitch in the Triple-A All-Star game, and then be eligible to return and start the fourth game after the break (keeping him up would mean he wouldn’t make a start until the third game after the break, unless they moved him up in the rotation, which is unlikely). As for bringing him back, if he can show the tendency to trust his curveball early in the count, and executes it enough times like he did today, then I think he would be ready to be up for good.
**With all of the prospects coming up, new draft prospects entering the system, and our normal live coverage, now is the best time to subscribe to the site. Glasnow’s debut is over, but tomorrow I’ll have exclusive coverage of Nick Kingham’s first rehab start down in the GCL. Video and a recap will be available to subscribers. You can subscribe to the site here.
**The Book on Tyler Glasnow. My very detailed article with Glasnow’s scouting report. This is my favorite series on the site, and I think it would be worth the subscription alone, just to get this much detail on each player that gets called up.
**Tyler Glasnow Shows His Potential In His Major League Debut. Brian Peloza had the live coverage of Glasnow’s start today in St. Louis.
**Pirates Notes: Familiar Faces Greet Tyler Glasnow on Debut Day. Prior to the start, Brian looked at how Glasnow has reunited with some old friends in the Pirates’ locker room.
**Prospect Watch: Live Report of Mitch Keller Getting Back on Track. On the minor league side, John Dreker had live coverage of Mitch Keller tonight, and he picked a perfect night to see him, as Keller looked great.
**Morning Report: Mitch Keller Has Struggled Recently Despite Solid Overall Stats. Prior to that start, Keller had been struggling, which John broke down in the Morning Report.
