Los Angeles Angels of Anaheim reliever Robert Coello’s forkball is all the rage. The pitch pictured above in .gif form may look like knuckleball, but it’s actually an “original forkball”, as Baseball Nation‘s Rob Neyer refers to it.

Neyer wrote about Coello’s ‘WTF’ pitch, as his catchers call it, and the history of the forkball last week:

It looks like a forkball before he throws it, but a knuckleball after he throws it. I’m not saying that nobody’s thrown that pitch in recent memory, because before all the video and the guys record stuff from video, all we had were words and sometimes words fail us.

But this, my friends, is the original forkball. The forkball we know — a slightly slower split-finger fastball, but still with quite a lot of spin — is not the original forkball. The forkball we know was invented … well, I’ve never been able to figure out exactly when.

Yahoo! Sports’ Jeff Passan elaborated on this mind-bending pitch, and some of the physics involved in throwing it. He also includes some quotes from Coello and Angels’ catcher Hank Conger, in which they discuss the unpredictable nature of the pitch.

Here’s a video, which will surely be pulled from YouTube, highlighting Coello’s WTF pitch: