Below is an instruction that describes a task. Write a response that appropriately completes the request.

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

### Inputs:
table_name: table, columns: ['Week', 'Date', 'Kickoff', 'Opponent', 'Final score', 'Team record', 'Game site', 'Attendance']

### Response:
SELECT Opponent FROM table WHERE Game site = Waldstadion AND Week = 6