user: Question: What was the name of the opponent when the method was KO (slam), and record was 13–1?
Columns: ['Res.', 'Record', 'Opponent', 'Method', 'Event', 'Round', 'Time', 'Location']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Loss', '45–9', 'Josh Koscheck', 'KO (punches)', 'UFC 135', 1.0, '4:59', 'Denver, Colorado , United States']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Method" = 'KO (slam)' AND "Record" = '13–1';