Throw harder?

In early January, I listened to a podcast show. In the show, the hosts and a guest, who worked in a baseball club in the majors, were talking about possible reasons that lead to pitcher injuries.

 

There are several possible reasons. And they indicated that pitchers are throwing really hard nowadays and that might lead to a higher probability of injuring a pitcher’s elbow or shoulder. Throwing harder, well, that really made me wonder whether pitchers are throwing harder these days.

 

To solve my doubts, I decided to check on the statcast website.

Firstly, I decided to check on four-seam fastballs. Back in 2008, average velocity of four-seamers was below 92 mph. In 2009, the average velocity of four-seam fastballs went up to 92.1 mph. Since then, the league wide average velocity of four-seamers had remained above 92 mph but below 93 mph for several seasons. In 2015, the average velocity of four-seamers increased to 93.1 mph. From 2015 to 2022, the league wide average velocity of four-seam fastballs remained between 93 mph and 94 mph. Nonetheless, since 2023, the average pitch velocity of 4-seam fastballs has jumped to over 94 mph.

In addition, let’s take a look at spin rate. The spin rate data has become available since 2015. In 2015, the average spin rate of four-seamers was 2239 rpm. The next year, the number was over 2260 rpm and it had been at least 2260 rpm for 3 seasons. In 2019, average spin rate of four-seamers in the majors was 2289 rpm and in 2020, the number was over 2300 rpm. In 2021 and 2022, average spin rate of four-seamers was 2274 rpm. Over the last 2 seasons, it went up a bit again.

 

Finally, let’s take a look at the number of four-seamers that reached 95 mph or higher. Back in 2008, 41000+ four-seamers reached 95 mph or higher. In 2009, the number was over 44000. From 2010 to 2012, the number didn’t reach 44000. Nonetheless, it remained over 40000. However, in 2013, there were more than 50000 four-seam fastballs that were at least 95 mph. The next season, it went up a little bit. In 2015, there was a huge jump. In the league, more than 65000 four-seamers reached 95 mph or higher. In 2016, the number was even higher. But, in 2017 and in 2018, it dropped a little bit. Nevertheless, in 2019, there were 70000+ four-seam fastballs with a velocity of 95 mph or higher. Well, the 2020 season was a shortened one. In 2021, 70000+ four-seamers reached 95+ mph again. In 2022, more than 80000 four-seamers were 95 mph or higher and the number increased a lot in 2023. Last season, in the league, there were 90000+ four-seamers with a velocity of at least 95 mph.

From 2008 to 2024, as we can see, the trend of four-seamer’s velocity is going up and the average velocity of 4-seamers was over 94 mph in 2024. Well, average spin rate changes, in particular, MLB implemented a new policy of using foreign substances in 2021. After the new policy, average spin rate drops. However, it went up again recently. Moreover, a key thing is that there are more and more pitches that reach 95 mph or higher. Over the last 17 seasons, only the 2020 season was a shortened one. Hence, given that there weren’t huge differences in total pitches thrown each season and it’s quite clear that we are seeing four-seamers that are getting faster.