What should we call Rivera’s other fastball?
by Mike FastOctober 04, 2009
Mariano Rivera is famous for his cut fastball. So famous, in fact, that it's a common misconception that he only throws one pitch. Of course, from PITCHf/x data, as well as some newspaper reports, we know he throws another type of fastball. I've often seen it referred to as a sinker or two-seam fastball, but its spin deflection certainly looks like a classic four-seamer.
In a discussion about Dave Allen's post about Mariano Rivera that took place at the Book blog, I had the occasion to look for images of Rivera's two fastball grips. I thought I'd share them here for yuk-yuks with the other two of you in the world who care about what to properly name Rivera's "other" fastball.
First, here's his cutter grip, with index fingertip and middle fingertip on the seam. As far as I can tell this is close to a typical cutter grip--a four-seam grip with the ball set a little off center in his hand. (There's a better picture here, but I don't have permission to post the image.)
 |
| Rivera throws a cut fastball against the White Sox, July 16, 2006. (Icon/SMI) |
Now, here's the other fastball, the one I tend to call a four-seamer because of how it moves. It's the one others call a two-seamer, though I'm not sure why. If you look at how many seams he's holding, should we call it a one-seamer?
 |
| Mariano Rivera throws his other fastball against the Rangers, August 7, 2008. (Icon/SMI) |
Mike Fast is a Royals fan who enjoys investigating baseball questions using data of many sorts. He is a member of Complete Game Consulting. He welcomes comments via e-mail.
I think I remember something in an article from Driveline Mechanics about Jon Lester throwing a one-seamer….