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

### Instruction:
Who is the opponent in the final when frankfurt is championship and the year is less than 1993.0?

### Inputs:
table_name: table, columns: ['Outcome', 'Year', 'Championship', 'Surface', 'Opponent in the final', 'Score in the final']

### Response:
SELECT Opponent in the final FROM table WHERE Championship = Frankfurt AND Year < 1993.0