In a 2018 webinar, Rickson Gracie was asked about his toughest fight ever. His answer was insightful and somewhat long, so we'll keep the intro short. Enjoy:
"Definitely, my worst fight was my first MMA fight with Zulu, in which I was 19 years old with no previous MMA experience—only fights on the streets, or training in the academy, but I had no experience in MMA. And the guy was already at 120 fights and four draws, and 120 victories. He was just a monster with a lot of experience. So when I started with this fight, I was really getting a new experience in my life.
"And right at the beginning of the fight, I could hit him with my knee on his face, and in my mind I thought, 'Oh, I win the fight.' But I was totally wrong; he stood up, shook his head, spit out a tooth, and walked to me like nothing happened; I said, 'Wow.' It was terrible: 'It doesn't work.' So he's coming to me; and for the next nine minutes, because it was ten-minute rounds, we're going like crazy, and he throws me out of the ring, and I come back, and I go to his back and kick him, and he pulls... So it was a crazy fight.
"And at the end of this first round, I was completely exhausted; and I crawled to my corner and said to my dad and my brother Rolls, 'Guys, I cannot go back there. I'm dead.' And my dad didn't even listen to me; and I said, 'Dad, I'm serious.' 'Oh, you're doing good.' I said, 'Dad, I'm serious. It's hard for me to go back there. I cannot—' So as I start to explain my case, my brother throws a bucket of ice and water on my head. And then they push me out, and I'm already there with the black guy again.
"And fortunately, it was as my dad said to me: he was as tired as me, and I could get a position, he could not defend anymore, and I put him to sleep, and I win the fight with three minutes in the second round. So, the worst thing for me was not the fight; the worst thing for me was how I decided to quit in my mind. Because I thought I could not have more chances. And my mind was my worst enemy. And my dad proved me wrong. Thank God my dad, my brother was there to make me feel like, 'B.S.! Just keep going.'
"And finally, after this fight, I realized my worst enemy was in my mind, playing tricks on me. So that was my biggest lesson, was my biggest nightmare on the mat, because when you stop believing, you lose track of everything around. So, after that, I turned on the switch that I prefer to die rather than quit; and never, ever did I have the doubt in my mind I have to do 110 percent there. And if something happens that doesn't go with what I believe, I'm not gonna tap, I'm not gonna quit—I just prefer to surrender. So, with that mindset, I continued my career with a lot of success. But it was not exactly the techniques applied; it was more the way I think about the tradition, my responsibilities with the family, and the capacity I have to surrender to God, giving my soul, giving my body to represent what I believed at the time. So, once the quitting aspect in my brain was dead, I'd become the happiest fighter in the universe."