He had a 45% whiff rate on the 4 seamer in the AFL. One breakdown I’ve seen has suggested that he uses the 4 seamer up early to steal an early strike and then uses the sinker like a change up as it has a lot of separation from the 4 seamer.
“Here's some approximations of his pitch metrics from the AFL, based on his pitch plot from prospectsavant.com (though Statcast had trouble classifying his pitches):
4SFB: 95 mph, 15" iVB, 9" HB
SINKER: 95 mph, 6" iVB, 16" HB
CURVE: 80 mph, -10" iVB, -12" HB
CUTTER: 90 mph, 7" iVB, -1" HB“
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