MLB Best fastball: The Best Fastballs of 2018

With pitching at an all-time great level it is fun to look at individual pitchers and their arsenal to see which pitchers have the best pitches. What follows is an attempt to illustrate the best fastball in 2018.

Over the next few weeks, I am going to be rolling out this series documenting the best pitches in the major leagues in 2018 starting with four-seam fastballs. I won’t be looking for the best individual pitches but more the best overall body of work with a particular pitch. For now, these lists will only include starting pitchers as they not only provide a better sample, but they also have to work through lineups several times per start. This makes what a starting pitcher does with his pitches more impressive. These rankings are comprehensive based on several different aspects of the pitch. I won’t simply be ranking fastballs based on velocity, but also several other metrics deemed to be valuable to a productive fastball:

Velocity

Velocity is likely the most obvious factor here. The harder a pitcher throws, the less time the batter has to react to the pitch. Many people will try to say that the reason for the rise in strikeouts in baseball is because the hitters do not care about striking out anymore. There is some truth to that but the main cause for the steady increase in strikeouts over the years is the just as steady rise in velocity. Pitchers are throwing so hard these days it’s near impossible for hitters to catch up. Velocity is clearly important to a good fastball, but I would argue it is not the most important evaluative criteria.

Effective Velocity

Effective velocity is the hitter’s perception of the speed of the pitch. This is mostly based off of the pitcher’s release point. If the pitcher has a long stride and releases the baseball closer to home plate, his 90 mph fastball is going to get there quicker than a pitcher with a short stride who releases the pitch from further away. Effective velocity is probably a more important factor than radar gun velocity because it is what actually affects the game. However, I believe that there is still enough value in regular velocity to include them both in this exercise.

Spin Rate

Spin rate is a newer concept at least to the general baseball audience, but it has been proven to be quite the important factor to pitch performance. Fastballs thrown with a higher spin will typically have what is perceived to be a “rising” action. These fastballs are often thrown above the batters hands to create swings and misses. A low spin fastball will have sinking action and will be hit into the ground more often but will result in less whiffs. The problem area is a fastball thrown with medium spin where there is not enough spin to create the rising allusion but too much spin to sink properly. These are the fastballs that get hit hard. In the past four years since we have had Statcast data we have learned how important spin rates can be.

Movement

Movement is inherently one of the most important aspects of any pitch. It doesn’t matter how fast a pitch is if it’s too straight. Good late movement can be the difference between a swing and a miss and a 450-foot home run. Four-seam fastballs are of course the straightest of all pitches, but there is still a difference in fastball movement from pitcher to pitcher. Good moving fastballs are key for pitchers who cannot simply rely on elite velocity.

Whiff Rate

Swing and miss rate or “whiff rate” is the percentage of times that a batter swings at a pitch and misses. This is one of the single most important pitching statistics as it is a statistical illustration of how nasty the pitch is to the hitter. Ground balls are great but no damage can be done on a pitch that is never hit.

Ground Ball Rate

There is no slug on the ground. With hitters trying to elevate the ball more than ever in today’s game, it has become increasingly important to keep the ball on the ground. Ground balls are a pitcher’s best friend even in an era of increased strike outs. Pitchers that can keep the ball on the ground especially with their fastball have a distinct advantage over fly ball pitchers who are more prone to allowing home runs.

xwOBA

Expected Weighted On Base Average for my money is the ultimate per plate appearance pitching stat. It takes into account strike outs, walks and balls in play based on their expected outcomes. Using expected outcomes is much better than actual outcomes because there are so many random and lucky things that can happen on a batted ball. Giving the pitcher credit for these things that are out of his control is simply the wrong way to look at it. Looking at xwOBA allowed by pitch type will give us an idea of how well the pitcher was able to produce the kinds of batted balls that typically result in outs.

Without further ado, I present the top fastballs by starting pitchers in 2018: