Agree, nothing to home plate, minimal leg drive, everything rotating together, no hip to shoulder separation. He’s trying to make up for it with an aggressive glove tuck to whip his shoulders around and then his arm yanks down. If he’s throwing 85-87 it’s all about mass, because that motion is not helping anywhere. he’s all rotation, no drive. My guess is he’s missing high and then in the dirt when he over compensates.
The good, his arm path and timing on his arm cocking, as well as opening of hips. A good strong front leg until he rotates over it towards third base.
My suggestions: He really needs to bring the trunk towards his target against that good front leg,
- counter rotate trunk to delay shoulder rotation, just prior to drive portion (ie help stay closed with shoulder)
- drive at the point he can’t hold forward momentum from opening his front side, this will help open hips first (feet in sync), upper body stay closed. At this point any degree of separation will help.
3.rotate glove thumb from down to up and raise throwing arm to cocked position, leave the glove out front to help block off that excessive rotation
- Bring chest to glove, lay arm back
- Release arm into throw, pronate and finish
I don’t mind his shoulder tilt since he throws from a high slot, just don’t over do it.
Separation is usually associated with velocity but I also believe it helps the upper body from over rotating so that it can slam forward towards target, helping keep ball in line and more on target. that way timing is a high or low thing vs. all 4 directions.
The aggressive glove tuck is the result (or a compensation) of/for a poor leg drive and momentum towards home plate. Not the root cause of his control problems.