Book excerpt -- 'RISE: Surviving the Fight of My Life,' by Paige VanZant

MMA fighter Paige VanZant had to defeat obstacles in and out of the Octagon. Tim VanBergen Photography

Excerpted from the "Go Ahead, Underestimate Me" chapter of "RISE: Surviving the Fight of My Life," by Paige VanZant.

It's UFC Fight Night 80 at the Chelsea Cosmopolitan in Las Vegas, a well-known mixed martial arts event. Our fight is the main event. I have six wins on my resume, and I'm not backing down for my seventh. Because the strawweight division is new, I can be a world champion. The momentum has been building so much that it feels like Christmas, my birthday, and New Year's all rolled into one. I'm twenty-one, I'm fighting with the UFC -- my life is starting to feel like a sort of cosmic arrival. I settle in with myself, attuned to a path of growth, unwavering in my goals. Having such clear focus and direction gives meaning to every single day: I exist to evolve. And my intention feels volcanic. I walk onto the Octagon buzzing with a full-body excitement. I'm up against Rose "Thug" Namajunas, who was in The Ultimate Fighter and got her feet wet as a taekwondo black belt and jujitsu master all before the age of ten. Taekwondo is a Korean martial art with a strong emphasis on head-height kicks and jumping and spinning kicks; whereas jujitsu is more ground game. This means Rose is primed on every possible level, ready for any and all angles of attack. She's the number three UFC contender in the world and by far a more technical fighter than I am. Rose is beautiful, with her perfect Lithuanian facial structure and pool-blue eyes, an infectious smile, and a gorgeous head of hair -- which she shaves defiantly right before our fight. It's a fight. Not a beauty pageant, she tweets, her freshly buzzed cut featured on social media.

She takes me down during the first round and batters me with sharp elbows to the face. This girl is strong. My blood tastes warm in the spaces between the mouth guard and my teeth. The gash on my cheek is so bad it's not just bleeding, it's gushing.

"Keep breathing," my coach says as he slathers globs of Vaseline onto the cut to stop the bleeding, to no avail. "You're doing great. You have to stay mean for this one."

There's so much blood in my eyes and ears I may as well be fighting underwater -- everything is muffled and blurry. When we're on our feet she throws sharp, bullet-like punches, beyond my guard. None of the clinch takedowns I typically use are working on her. And as much as it stings to say it, she's a step ahead of me the whole time. It feels like Rose is in a whole other league of expertise, which might be a result of the fact that I was initially meant to fight Joanne Calderwood, who was forced to pull out five weeks ago and was replaced by Rose, who is currently destroying me. I'm reminded of Dad's warning that having heart is just one piece of the puzzle. Mastery of skill is the other piece, and Rose has got it on lock. I'm feeling defeated even before I lose.

In the next round, she gets me into a rear-naked choke so tight I have to remind myself to relax my throat, to take small sips of air through my nose, but I start seeing black spots and feel dizzy. Through a sliver of visibility, I catch a glimpse of the giant screen where the fight is projected and see myself, drenched in my own blood, my eye sliced open. I linger there in that zombie state for a moment and ask myself, Am I done? And still, I don't tap out. I survive the choke and the battery of fists that follow and when the horn blows, I'm as surprised as everyone else in the room that I'm not actually dead. I may not have the winning hand here, but I am calling up every drop of force I have to prevail.

By the fourth round, she already has six takedowns. Now she comes at me with not one but two deep arm bars, but miraculously, I manage to rotate my wrist and slither out from under her -- both times! She takes me down a seventh time. And an eighth time during the fifth round. And it's during this round that she gets me into a rear-naked choke with such a grip that there's no resisting the pressure on the bones in my throat. It is quite literally a life-or-death moment. And so I tap out and Rose wins by submission. The commentators call it the win of her career. At the press conference after the fight, I sit there all busted up and choke back tears. I ask my parents to leave because if they stay, I'll bawl the whole time. I hold myself as strong as possible, but the disappointment burns in me.

It's my first UFC loss and it feels like a little death. I hate losing more than I love to win, so when it happens, I have to mourn it, take it in and get my head around the lessons it came to teach me. And while the loss against Rose feels like a living hell, I discover that my grit during the fight did not go unnoticed. The fight commentators and media even say that while everyone remembers Rose's technical skills, they also remember my tenacity. In this way, I lost the fight but I won the respect of the MMA community. I keep reminding myself that this means something.

From "RISE," copyright Paige VanZant, courtesy of Hachette Books. The book is out on Tuesday.