A couple of things depending on the age of the player. If a teen, I would recommend the teen stand up and say NO emphatically, loudly, repeatedly--And of course report it to parents, school officials and anyone who will listen.
I used to tell our children, never, ever, ever allow someone to abuse you. Tell us, tell teachers, tell anyone who will listen--but keep talking.
We have to teach our children that nothing is worth accepting abuse. The coach should be removed and only complaints from the athletes will get the job done, unless a parent witnesses it and can step in.