Praise be to Allah.
If the blood that was taken from him was considered to be a small amount, then his fast is valid and he does not have to make up that day. If it was considered to be a large amount, then he should make up that day so as to avoid an area of scholarly dispute, and so as to be on the safe side and be sure that he has fulfilled his obligation.
And Allaah is the source of strength. May Allaah send blessings and peace upon our Prophet Muhammad and upon his family and companions.