user: Question: What is the average Loss for the long of more than 12 with a name of opponents with a Gain larger than 1751?
Columns: ['Name', 'GP-GS', 'Gain', 'Loss', 'Long', 'Avg/G']
Types: ['text', 'text', 'real', 'real', 'real', 'text']
Sample row: ['Charles Scott', '13–13', 1208.0, 34.0, 56.0, '90.3']
SQL:

assistant: SELECT AVG("Loss") FROM "Table" WHERE "Long" > 12.0 AND "Name" = 'opponents' AND "Gain" > 1751.0;