Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_27374004_4 ( date_of_appointment VARCHAR, replaced_by VARCHAR )

### Question ###
When was the date of appointment by Hugo Broos?

### Accurate SQL ###

SELECT date_of_appointment FROM table_27374004_4 WHERE replaced_by = "Hugo Broos"