Yesterday I wrote about Hunter Greene’s appearance for the Cincinnati Reds in instructional League. He was sitting 99-101 MPH with his fastball. At the time that I wrote up the article yesterday, there wasn’t a report on how his day had gone. Instead, I focused on writing about the velocity and the reported spin rate, and what it could mean.

Today we saw Fangraphs post the full outing, which didn’t make it an entire inning (reached his pitch count – the inning was ended because of it). Here’s the video:

As you can see in the video, Hunter Greene didn’t have the best day on the mound. The first batter of the game doubled down the line. A ground out to shortstop followed from the second hitter of the inning. The third batter would triple. He walked the next batter. The fifth batter of the inning struck out on a breaking ball. An RBI double followed and the inning was called due to the pitch count being reached.

It’s worth noting that instructional league is called that for a reason: It’s about taking instruction. Guys are working on very specific things at times and it seems like for Hunter Greene, on this day, it was his offspeed stuff. You obviously would have liked the results to be better than they were – but they don’t really mean much of anything in what turned out to be an absolute slugfest of a game.

Correcting an error

In the article written yesterday I linked to an article with some data in it regarding the spin rates of Major Leaguers. It wasn’t the correct link and was showing information that could have been misleading. As noted yesterday, Hunter Greene’s fastball spin rate according to Fangraphs Eric Longenhagen was about 2200 RPM yesterday. In the article I noted that was a little bit low for the velocity in which he was throwing. That part is indeed correct, but the article that I linked to didn’t have that information in it directly. I just wanted to clear up some confusion there. To expand on that, I’ve run the data for pitchers in the Major Leagues in 2017 and their spin rates on fastballs.

Velocity Spin Rate
97+ 2333
96-96.9 2276
95-95.9 2285
94-94.9 2260
93-93.9 2233
92-92.9 2201

Once again it’s worth noting that the group of players throwing 97+ is very, very small. The sample size for the group of guys throwing 93-94 MPH is three times larger. The same for the group from 92-93 MPH. While the correlation isn’t very strong, there is one between throwing harder and higher spin rate on the fastball. Grouping players by the velocities on 1 MPH intervals shows that – but within the specific groups you do see both higher and lower spin rate guys. As a quick refresher: Less spin = more sink and more spin = more “rise”. More spin, in general, leads to more swings-and-misses in the Major Leagues. With that said, it’s not the fastball that generates the most swings-and-misses for hardly any pitcher alive, it’s the secondary stuff. Spin rate, particularly on the fastball, isn’t nearly as important as a lot of other things (control, velocity, deception).