Excuses are not tolerated. Think about it. He's off the team. Players know this, and they make every effort to excel every day. They do so even more, and even play while they're injured, if they have aspirations to be on a professional team.
Blacks thrive in an environment of ruthless competition and demanding standards.
There may be some gains from applying a similar environment in the academic arena. Maybe we ought to have demanding schools where youngsters are loaded up with lots of homework, frequent tests and top-notch teachers. In such schools, there would be no excuses for anything. Youngsters cut the mustard or they're kicked out and put into some other school. I'm betting that a large number of black youngsters would prosper in such an environment, just as they prosper in the tough sports environment.