Have you seen all the technological advancements made in recent years? High-speed cameras, pitching labs, weighted ball training, wind tunnels – Maybe the reason we haven't sent anyone to the moon in decades is that we are using all the techniques to hit the batsmen. Obviously, the arms race (get it?) is beneficial for technically savvy, complex, and difficult to understand mathematical modeling.
This is an opposite, though: maybe you should just throw a fastball and a slider and then smile. A good example: Randy Rodríguez is the best reliefist in baseball this year, and he has no fantasies about his game. He threw a 98-mile fastball. He threw a nervous slider. That's it – anyway, that's actually what he needs. With eight appearances this year, he has 13 strikeouts, zero walking and zero running.
Oh, two paragraphs don't write articles? Well, I think we should have some extensions to everything. First, his backstory: Rodríguez signed with the Giants in the Dominican Republic in 2017, and then slowly climbed to the minor league ranks. He was a reliefist for high jumps, only the occasional Dalliances had a brief start, and he received the taste of Triple-A in 2022, where he was shelled. He tried again in 2023 with better results, and by 2024, he looked like he belonged to him. That was his first year as a minor, and the unit walking rate was that the giants were waiting. They called him mid-season and inserted him into the bullpen.
Wildness is usually the territory of the reliefist. The appetizers are consistent and smooth. Relief is the effort of Herky-Jerky and Max. This is not universal truth– Mariano Rivera's delivery may put the baby to sleep–but it's a good rule of thumb. I'm not a kinematics expert, but Rodríguez's delivery certainly looks complicated and can create some wildness. He had leg kicks, some torso rotation, long arm swings, and even a little firefight. This is his first fastball of the year:
Are you surprised to see the tall sail? I'm not. But Jeimer Candelario is; he almost waved on that clear ball. That's because Rodríguez's fastball is completely electrical. Of course, he had to swing a lot of body parts to generate this power, but it paid off with uncomfortable swings and awkward speed. You should not be able to throw a fastball on this track and strike it:
I haven't told you that you haven't heard anything yet when it comes to good four-slit fastball shapes. Remember all these technological advancements? They show us that high-induced vertical fractures, shallow vertical direct close angles, and unexpected movements of a given arm slot are all very valuable. Rodríguez's heater dropped by two to three inches, given his arm slots and speed. And this combination itself is very rare. So far, 195 pitchers have pitched at least 50 fours in 2025. Only eight release the ball from a lower height and have a higher release point. In other words, he was releasing the ball from the side ball hand but threw it out of the arm slot of the three-thirds tall.
How is it like? He only had 5 feet 11 help. As part of his childbirth, he strides forward, which is even more helpful. The bigger the stride, the closer the torso is to the ground when released, and even the release point can make the arm angle higher. This is the delivery of a computer program dream.
Oh yes, our computer programs love it. PitchingBot believes it's one of the 15 best four players in baseball, and Ryan Helsley's fastball clone is more or less. Stuff+ thinks it's better than this. The biggest change this year is the order. Of course, this is hard to define, but it is a straightforward way of thinking. On the two-ball figure, Rodriguez threw a fastball 52% of the time last year. That sucks; the league average is 58%, and pitchers in the area that hit very few and still outstanding are mostly not worried about three balls as many pitchers than the rescuers. This year, he has a 62% intra-area ratio against fastballs in two-ball counts. This is necessary for someone who is even now easy to navigate a fastball or two.
Will Rodríguez maintain his own 0.0% walking rate? Obviously not. I don't even buy him as a plus. There is no evidence that the eight samples are greater than the contrary. Of course, he is improving over time, but his average walking rate is not a Logan Webber-level order compared to the 2024 table. In my mind, his fastball is the 70 items/50 command on the scout scale. It won't always be in the right place, but when it looks like this:
Hey, it's good. But it's “good fastball” good, not “zero ERA zero FIP” good. The real key to Rodríguez's success is his “secondary” tone, and my offer is because he happened to throw 50% of the time this year. That's a mutation slider, between the gyroscope and sweep, which turns the batsman into an inconsistent nincompoops:
Compared to the benefits of fast balls (speed, shape, angle), it is difficult to explain in a few words what makes the slider good. But it's easy to explain why Rodríguez is good: It moves more than just a gyro slider, but goes to home plate faster than a sweeper. This combination – coupled with the fact that he paired it with elite fastballs, makes batsmen destroy regularly. How to do it regularly? What is the 22% swing strike rate?
Yes, that's it. Therefore, 56% (!!!) chase rate will also be. So far this year, batsmen have only 58% of sliders In the strike area. In other words, you can cover them, and they can also figure out who meets the best. The slider may be a little worse on our pitch model, but it still easily shows above average and my eyes tell me the same thing. A slider for a guy who throws 92? Honestly, it's good. Slider with octane level of Rodríguez? Terrible.
To be fair, I should tell you that chase and area swing rates are misleading. That's because Rodríguez trusts his slider so much that he often throws it when he's behind. He didn't pitch completely backwards, but at least, he leaned:
Have been working so far. The batsmen believed that a man with a reputation for wildness would use his fastball in the strike zone at the first sign of trouble, but Rodríguez flipped the bent stuff and confused their trend. I don't know if he'll get rid of it forever, but the batsman is absolutely unprepared.
Now, I don't usually offer a stable diet of 1-0 sliders for a double-digit career walking rate. But what can I say? Rodríguez is on the stadium on the rope this year. When he was behind the number, he found the slider 70% of the time. Small sample? Definitely 17 sliders. But it is the elite realm of the true commanding artists living in. No wonder he wasn't walking anyone – he pitched like Brian Wau when he was behind.
Will all this continue? Obviously not. That's not how baseball works. But I'm confident to say that Rodríguez's pitching so far this season is like he's one of the top five or so reliefists in the game. Not smoke or mirror. The batsman is not playing balls below the middle to achieve an unimaginable strikeout. That number says Rodríguez has been one of the best pitchers in baseball this year – whether you're looking at the times or going deep into the weeds.
By the way, did I sell you an introduction to ignore pitching development and keeping the old school? This is nonsense. Old school and new school say exactly the same thing to Rodriguez. Ask any scout who sees him in a minor, but don't let them look at a laptop or a collaborative sports account and they will say “Great stuff, need to learn commands”. Ask the algorithm literally what he looks like this year and it will say “Great stuff, learned commands”. At least that's what we both said. So, will Rodríguez continue to be the best reliefist in the game? Probably not. Things are always changing, no one stays on it forever, and I can't imagine him continuing to master the ball like this. But is all this fluorine? Absolutely not. His performance is as good as his two main courses, and the precise command points out.
All statistics are as of April 14.
