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

### Instruction:
How many 1st leg have team 1 ofk belgrade?

### Inputs:
table_name: table, columns: ['Tie no', 'Team 1', 'Agg.', 'Team 2', '1st leg', '2nd leg']

### Response:
SELECT COUNT 1st leg FROM table WHERE Team 1 = OFK Belgrade