Q.  IS this a "cutter" or a "Four Seam Fastball With Ridiculous Movement?"

A.  4-seam fastballs break armside 5 inches, and up (relative to vacuum) 8 inches.  I would use "Four Seam Fastball With Ridiculous Movement" to describe something that broke OUT a lot more than 5 inches or UP a lot more than 8 inches, wouldn't you?

Brandon Morrow's four-seam fastball rises, at times, 12 inches.  That's a "Four Seam Fastball With Ridiculous Movement."  It moves in the direction that a 4-seamer does, but more so.  Isn't that what "Four Seam Fastball With Ridiculous Movement" describes?

On the other hand, Roy Halladay's "cut" fastball - which I'm sure he holds with four seams - moves in a direction that is not the same as a 4-seam fastball.  Instead of breaking armside 5 inches, it breaks gloveside 1 inch, on average.  

Halladay's cutter is not called a "Four Seam Fastball With Ridiculous Movement".  It's called a cut fastball, because it cuts in on lefties.

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Q.  How far does Felix' cut fastball break in on lefties?

A.  Here's the cluster chart from his last start.  

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His cutter averages +0 inches of horizontal movement, one inch less than Halladay's.  Some of his cutters run in 2-3 inches on lefties; some of them stay armside an inch or two.  

As you can see, the pitches are clustered.  Felix' actual four-seam fastballs are in the red circle, from the catcher's point of view.  The changeups are in the blue, and the cutters are in the green.

There is more overlap between Felix' 89-92 four-seam fastball and his 88-90 changeup than there is between his fastball and his cutter - not just on this date, but on every date.  It is easier to distinguish Felix' cutters than it is his changeups; his cutter is a more distinctively identifiable pitch than his changeup.

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Q.  Does this indicate that Felix is deliberately throwing two different pitches, four-seamer and cutter?

A.  That clustering effect - the "no man's land" around 3-4 inches armside - would normally indicate that, at least, Felix was using different finger pressure as he released the ball.

I've watched Felix' F/X's a whale of a lot, and I've often gotten the impression that Felix himself does not know which way the ball is going to move.  One day his fastball will rise 8" relative to gravity; the next day his fastball will drop like an anvil, registering only 3" of vertical movement.

It's possible that his "cutter" takes its shape for no reason other than that he puts the pressure on his middle finger as he lets go.  If that's true, (1) I hope he doesn't forget how to do it, and (2) the spin on the ball still conforms to the definition of a cut fastball.

As with Daisuke Matsuzaka ten years ago, the key to Felix' greatness seems to be in his fingers, not in his arm.  That 89 MPH "changeup" .....  :shakes head: I'll bet you that Felix' handshake is strong enough to crumble bricks.

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:shrug:  What does Mariano Rivera do to make a fastball cut?  He holds it with four seams, and says that he can't teach it to anybody, because the Creator taught it to him.

We're down to arguing about finger pressure to define a pitch.  I suggest we stow the finger-pressure definitions and use the F/X system we've agreed on.  If it sails out and up, it's a 4-seamer.  If it sails out and down, it's a 2-seamer.  If it sails in, it's a cutter.  Didn't we already agree that the flight of the ball was what we'd use?

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Q.  Anyway, the pitch bites in on lefties, and Adrian Gonzalez reports this to be a rather substantial problem for hitters.

A.  All of which makes Felix' start tonight the more exciting.  :- )  Anonymous, below, asserted that Felix is on the first two-start run ever, for 10+ K's.  If he comes out and deals again like he did in Boston...

Who knows.  I'm fancying the idea of Felix leaping a big plateau here, and tonight's start will be telling.  Certainly his 9.3 K, 2.6 BB, and 0.7 HR line is already the best he's ever had.

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