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

### Instruction:
When did nswrfl has a score of 8-21?

### Inputs:
table_name: table, columns: ['Year', 'Opponent', 'Competition', 'Score', 'Venue', 'Attendance']

### Response:
SELECT Year FROM table WHERE Competition = nswrfl AND Score = 8-21