you need to get under and behind the ball and square up the hit point
on the serve you could pull back across the waist like a quarterback
Thiem has a monster backhand== he coils the tip of the racquet past his back hip
when you are getting jammed pull your hands in– a Dusty Baker tip
on the forehand side the range extender shot is slice shot which is often called a squash shot — get the ball back one more…
we are not kidding about the back knee must be under the incoming flight path
to get the body rotation you must get the front foot pointing slightly forward–if you cross over too much you block the rotation
on the hit you want to be under and behind the the hit point and square up the racquet
on your preparation dip the racquet tip to the ground to increase getting below the ball and get more low to high swing
on the high incoming shot — start your preparation below flight path but higher
on the two handed backhand get both elbows up on the rotation
even when you are stretched out you must keep the racquet level
the serve hit is up and out– a quarterback release
even on the slice shot you must still be under the flight path and behind the ball
after after the hit keep your eyes where the ball was for a beat