Hayford was initially placed on administrative leave last week ... after Stadium Basketball Insider Jeff Goodman reported that the coach had used the racial slur during a scrimmage.

According to the report, Hayford -- who is white -- said the n-word last Thursday after a player had used it.

Goodman reports this was not the first time Hayford had been accused of using the term around his team.

Hayford reportedly apologized to his squad over it all on Nov. 6, but according to Goodman, some players refused to accept the mea culpa, and ultimately vowed to never play for him again.

Seattle U's Athletic Director, Shaney Fink, issued a statement Thursday announcing Hayford's resignation, saying, "It is clear to me that coach Hayford is no longer able to effectively lead this team."

"The top priority within the Athletic Department is, and always will be, to support the wellbeing and success of our student athletes -- in and out of the classroom and in their chosen sport."

Fink continued, "We are committed to advancing an athletic community that is inclusively excellent. We will take additional steps to ensure any concerns within the program are addressed and that all our student athletes are seen, heard, and supported."