Breaking ball
Slutter (Cut-Slider)
A cutter and a slider blended into one. It's harder and tighter than a slider and holds its fastball look longer, but breaks glove-side more than a cutter. It blurs the two so much that tracking systems keep flipping the label.
The grip
A blend of a cutter grip and a slider grip — released to fall between a true cutter and a true slider rather than as either one cleanly.
What it does
Sits between a cutter and a slider: harder and tighter than a slider and holding its fastball look longer, but with more glove-side movement than a cutter. Because its speed and shape overlap both pitches, tracking systems often flip the label between cutter and slider for the same offering.
Tyler Glasnow has publicly used the name 'slutter' for a hybrid of his; one outlet (Korked Bats) reported his version as a splitter-cutter while others describe a cutter-slider, so the precise blend behind the nickname is contested. The cut-slider sense used here is the broadly described one.
Who throws itTyler Glasnow has discussed his own version; Jake Arrieta's breaking ball has been cited as a tracking example
Basic file
This pitch has a sourced one-line grip and movement and an honest explanation — not yet a filed specimen with authored grip geometry and a full craft chapter. A fuller breakdown is coming. Sourced, not corrected.