Saying a racist word does not in fact make you a racist Tubey, that's what Poyet was saying and any person with common sense would say the same.
He didn't support racism.
It does if it was said with negative intent.
For example, use of a certain word on South Park doesn't make the makers of South Park racists, because it was used for parody purposes with full knowledge of the meaning of the word.
However, Suarez racially abused Evra with negative intent.
Suárez's use of the term [negro] was not intended as an attempt at conciliation or to establish rapport; neither was it meant in a conciliatory and friendly way.
It was racism. At that moment in time, Suarez was being racist.
By defending Suarez's actions, Poyet is defending a racial abuse and supporting racism.
Again, that's not to say he is a "racist", nor is it to say Suarez is a "racist" now. But Poyet was clearly supporting racism.