user: Question: Who was the fight against when Loss was the result at the Gladiator Challenge 87: Collision Course event?
Columns: ['Res.', 'Record', 'Opponent', 'Method', 'Event', 'Round', 'Time', 'Location']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Loss', '4-4', 'Mike Hayes', 'Submission (verbal)', 'Palace Fighting Championship: Best of Both Worlds', 2.0, '1:01', 'Lemoore, California , United States']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Res." = 'Loss' AND "Event" = 'Gladiator Challenge 87: Collision Course';