MLB superstar Trevor Bauer is currently under investigation for assault ... after a woman claims the Cy Young winner got physical with her earlier this year.
But sources close to the case say Bauer is adamant the encounter was nothing more than consensual, rough sex.
TMZ Sports has learned the alleged victim was granted a temporary domestic violence restraining order earlier today in L.A.
Pasadena PD is investigating the alleged incident ... and sources tell us TB is cooperating with authorities.
As for the alleged victim .