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_27893892_2 ( opponent VARCHAR, game_site VARCHAR, week VARCHAR )

### Question ###
what was the opposition where the field is waldstadion during time 6

### Accurate SQL ###

SELECT opponent FROM table_27893892_2 WHERE game_site = "Waldstadion" AND week = 6