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

### Instruction:
During round 8 when the Position being picked was rb, what was the highest overall pick?

### Inputs:
table_name: table, columns: ['Round', 'Pick', 'Overall', 'Name', 'Position', 'College']

### Response:
SELECT MAX Overall FROM table WHERE Position = rb AND Round = 8