To be successful in something against the odds.
Phrase originated from the UFC fighter Randy Couture, who in his 40's managed to beat his opponents decisively when no one thought he stood a chance.
<Person 1> This guy is unbeatable. No one was even close to beat him... Sorry man but I don't think you stand any chance.
<Person 2> Well, I guess I'm just going to have to Couture him.
"I have 3 days 'till the exams, and I haven't studied at all. If I drink a lot of coffee and study day and night, I might pass it. It's going to be ruff, but I guess I'll just have to Couture it!"