Yovanny Cruz and Will Dion were both picked up by the Nats at the deadline, but they are very different pitchers. Cruz is a flamethrower who averages 100 MPH, while Dion only sits at 91. However, Dion’s fastball is more effective, and it is not even close. I wanted to look at why Dion’s softer heater is so much better.
Velocity is a very big part of what makes a fastball good, but it is not the only ingredient. Another key factor is the shape of the pitch, and that is where Dion stands out. Induced
vertical break measures how much movement a pitcher generates from how he spins a ball. For a fastball, the more IVB the better.
Dion averages over 20 inches of IVB on his heater which is an elite number. While a pitch can’t actually rise, for hitters it looks like Dion’s fastball is rising because it is fighting against gravity. On a lot of his strikeouts last night, you can see Mets hitters swinging under his 90-92 MPH fastballs.
Between the Guardians and Nats, Dion has a 33.6% whiff rate on his fastball, which is exceptional. Between the movement I have been talking about and how well he commands it, Dion’s 91 MPH heater plays way above its velocity.
That command is another reason why Dion’s fastball works. When you look at his location heat map on Baseball Savant, there is a big red zone at the top of the strike zone. This is exactly where you want to put a fastball that has a lot of ride. We saw Dion perfect this approach yesterday.
Dion’s other pitches, especially his changeup play off his fastball very well too. Out of his hand, Dion’s changeup looks a lot like his heater before floating off the table. The 13 MPH velocity gap between his fastball and changeup also flummoxes hitters. Dion is not over-powering, but he has a highly functional arsenal and very good command. That is why he has a 3.25 ERA and 33 strikeouts in his first 27.2 big league innings.
Yovanny Cruz, who the Nats also got at the deadline is a very different story. When you just look at his raw stuff, he should be elite. His fastball averages 100 MPH and his secondary pitches have crazy potential. The best sliders and splitters he throws are mind blowing.
However, he has really struggled with the Nats. A big chunk of this comes down to command, but his fastball is also nowhere near as good as the velocity suggests. Despite averaging 100 MPH, Cruz has not generated a single whiff on his heater at the big league level. He has thrown 51 of them, many in triple digits, but there has not been a single empty swing.
How can that be? Well, some of it is due to command. Unlike Dion, Cruz’s location heat map is all over the place on his fastball. Some of them are upstairs, some outside and some lower. He just does not really know where the pitch is going.
The shape is also a problem. Dion’s fastball has 20.1 inches of rise and 0.7 inches of tail. Meanwhile, Cruz’s heater has 12.7 inches of rise and 12.8 inches of tail. That is what folks call a dead zone fastball. The pitch ends up exactly where hitters naturally expect it to.
In 2026, hitters see enough velocity to have success against 100 MPH fastballs without any unique movement. Heck, when I watched Rochester play last night, I saw 3 guys hit 100 MPH and that is in the minors. Cruz’s fastball is hard, but it is poorly located and not fooling anyone.
That is why he decided to throw 13 straight sliders to end the game. He totally lost faith in his fastball for the reasons I mentioned. His slider is a much better pitch, but if hitters can completely take the heater out of their mind, it can get hit around as we saw.
So what is the fix for this? In my opinion, Cruz needs to get away from the 4-seam fastball. I would send him to the minors and get him used to throwing either a sinker or a cutter, whichever is more comfortable for him.
With Cruz already getting a natural tail on his 4-seamer, a sinker makes a lot of sense on paper. He can use the sinker to get quick ground outs, while he uses the slider and splitter to put guys away. That would be a functional arsenal even with mediocre command.
However, Cruz does not have a functional arsenal at the moment. He clearly does not have any trust in his fastball at the moment, and that is hurting his confidence. I am sure Cruz has been able to get by on velocity for most of his career, but right now that is not working.
In an era where everyone is hunting velocity, the cases of Yovanny Cruz and Will Dion are a good example of a less discussed factor when looking at fastballs. Velocity is cool, but fastball shape and command is also massively important. It is why Will Dion’s 91 MPH fastball gets whiffs a third of the time while Cruz’s triple digit heater does not get any whiffs.











