This story is excerpted from "QB: My Life Behind the Spiral" by Steve Young with Jeff Benedict. To buy the book, click here.

In Week 2 of the 1993 season, we traveled to Cleveland to play the Browns on Monday Night Football. Stomach problems continued to dog me, and early in the game, I took a pretty good shot that left a deep bruise on my left thigh. Cleveland was a lousy team. But it was as if Cleveland's defense knew our plays in advance. We couldn't figure out how they were doing it. I threw three interceptions and we lost 23-13.

It was a long flight back to San Francisco. My left thumb, left elbow and left thigh were all hurting. By the time I got to my loft it was five in the morning. I was so beat I didn't bother undressing and collapsed on my bed. But I couldn't sleep. My mind wouldn't let me. Losing to Cleveland? Unacceptable. Starting the season 1-1? Unacceptable. Six interceptions in the first two games? Unacceptable.

My thumb wasn't right. My elbow was sore. My stomach was a mess. I was fatigued. I had to play better.

I tossed and turned all night. I was still awake at dawn. Panic set in. My body craved sleep, but my mind wouldn't wind down. I closed the curtains, pulled a pillow over my head, and finally dozed off. But the slightest flinch woke me.

At 10, I crawled out of bed. My thigh felt like one giant charley horse. I gazed into a mirror and saw a man buckling under the weight of the world. The 49ers had to win this year. I had to deliver.

My outlook was perplexing. On the one hand, I had incredible confidence in my ability as a quarterback. I was the MVP of the league. Yet I felt tethered to a ball and chain. I was the quarterback of a Super Bowl-caliber team. I knew what had to be done. But in the second week of the regular season I already felt the heaviness of anxiety.

Steve Young won three Super Bowls and two MVPs in his career. David Madison/Getty Images

I went back to my bed and dropped to my knees and pleaded with God for help. I didn't want to do this anymore. But I also didn't want to quit. I still wanted to find out how good I could become. In the aftermath of Joe Montana, San Francisco was the hardest place in the world for a quarterback to play. But I still wanted to know: How far can I go?

For now, I told myself, You just have to survive.

I had been repeating this same mantra since high school. It had always seemed to get me through the seasons, but for some reason it wasn't doing the trick this time. For the next couple of days, I stumbled around in a fog. Finally, I called Carole Burr in Utah.

"I'm not going to make it through this season," I told her.

She stayed on the phone with me for hours. She'd been encouraging me to see a psychologist for a few years. This time she put her foot down. She said she was sending a doctor-friend to San Francisco. This time I was too mentally and physically exhausted to fight her.

Rex Kocherhans (pronounced CO-ker-hans) was a 38-year-old family therapist with a practice back in Provo. He showed up the next day at the Merrills' place, but by the time he arrived I had already left and checked into the team hotel. I was in my room with Brent Jones when Carol called and informed me that Rex was waiting at the barn.

The guy didn't even know me. Yet he had gone to the trouble of flying to the Bay Area on a weekend. I couldn't stand him up. I told the team I was sick and needed to return home for the night.

Kocherhans had an empathetic ear. We talked about my childhood, my family, my ambitions and my fears. I told him everything. He was pretty shocked. He asked if I had ever shared this with anyone. I told him I had gone to see a psychologist two years earlier. But I hadn't done any follow-up visits.

We ended up talking through the night until Rex nodded off. By that point the sun was coming up. I told him to help himself to the couch. I had to get ready to go to the stadium.

By the time Steve Young walked onto the field in Week 3 of the 1993 season, he hadn't slept in over a day-and-a-half. George Rose/Getty Images

That jolted him.

"You're going to go to the game?"

"Of course I'm going to the game."

"You haven't slept. You've been up for 24 hours straight."

"Well, actually, it's closer to 36, but I'll see you after the game."

"So you're choosing to go to the game, huh?"

"I don't want to go. I have to."

"Well, you don't have to go."

I smiled. He didn't get it. "I'm the starting quarterback for the 49ers," I told him. "I can't just not show up."

"They won't arrest you for not showing up," he said. "You have a contract, and there will be implications. But you don't have to go."

"I'm going to go to the game," I told him firmly. "But I'll make you a promise. If we win today, I'll talk to the team doctor."

Then I gave him a ticket to the game and said I'd see him afterward.

Sept. 19, 1993. It's warm and sunny at Candlestick, perfect football weather. But I'm a mess -- nausea and vomiting. Plus, I'm shivering and shaking. During pregame Dr. Klint thinks I might have gastritis or a bad case of the flu. He puts me on an IV. I don't bother telling him it's anxiety. Besides, I need the fluids. I haven't slept or eaten in almost 40 hours. I'm weak, tired, and yawning nonstop.

I feel like an uninvited guest at a house party when I walk onto the field. It's our first home game since Joe was traded to Kansas City. Fans hang signs of support for Joe all over the stadium. I read each one. I note that there are no signs supporting me.

Suck it up, I tell myself, and I start by completing six of my first seven passes. Then a linebacker hits me head on, planting his helmet in the crown of my helmet. I jam my neck, and there are black streaks from his helmet on mine. Under later NFL rules, he would have been penalized.

I keep going. By halftime I have two touchdown passes, but my head is throbbing and my neck hurts. In the locker room I get another IV before trying to battle back against Atlanta. With time winding down in the third quarter, we trail 20-16 and the crowd is uneasy. So am I. Desperate to make something happen, I drop back to pass from the Falcons' 8-yard line. I'm nearly sacked before scrambling free and spotting Ricky Watters in the end zone. I fire the ball. It hits defender Vinnie Clark in the chest and ricochets back toward me. The moment I see the ball in the air I run toward it, catch it, and head for the end zone before I'm dragged down at the 2-yard line. Finally, some cheers from the home crowd.

I expect a flag for catching my own pass. But the officials determine that a quarterback can complete a pass to himself. Apparently Y.A. Tittle did it once in 1959. On the next play we score to go up 23-20.

We hang on to win 37-30, but on our final play I am struck on the side of the head and I feel something pop in my neck. I walk off the field gingerly.

Despite being sleep-deprived, famished, and hampered by a jammed neck from a blow to the head, I have one of the best games of my career, completing 18 of 22 passes for 210 yards and three touchdowns. I also rush for 52 yards and catch one of my own passes.

Steve Young compiled 268 total yards against the Falcons, as the 49ers won 37-30. Otto Greule/Allsport

I stagger to the training room, where I undergo a neurological exam. Dr. Klint tells me that I have a jammed neck and a mild concussion. After some electro-stimulation, he gives me an anti-inflammatory and puts a cervical soft collar on my neck.

But my neck is the least of my problems. My emotions are on the surface, and I don't want anyone to see me this way. I lie on my back on the training table until everyone except Dr. Klint is gone. Then I sit up.

"Reggie, can I talk to you?"

He looks at me. Dry sweat and grass stains coat my skin. My hair is matted from my helmet.

"You look like you haven't slept in days," he says.

"I haven't."

He closes the training room door.

"Steve, what's going on?"

I bury my face in my hands and start to shake.

"It's okay, Steve," he whispers.

"Reggie, I'm really struggling."

"Yeah, I know."

I start sobbing. "What's wrong with me, Reggie?"

He puts his arms around me.

"I'm sure this doesn't make any sense to you," I continue.

"Steve?"

"What?"

"I understand," he whispers. "I had bouts of this all throughout my days in medical school."

I look up. Reggie is crying.

"I know all about anxiety," he says. "I understand how it works."

"Is that what this is?" I ask.

I hug him and wipe my eyes.

"I watch the other guys and I know what I'm feeling is different," I say. "I don't get it."

"I know."

I stay with Reggie for nearly an hour. He says he's going to arrange for me to go back to Dr. Stanley Fischman. This time he wants me to do more than go in for a visit. Reggie wants me to start seeing Stanley on a regular basis.

I promise I will.

Outside the stadium I meet back up with Rex Kocherhans, whom I have now known for a whole 24 hours. Laughing, he says to me: "So let me get this straight: You have so much anxiety that you can't sleep, but then you go out and play spectacular football?"

I shrug.

"In my professional opinion, you should keep this up," he says, laughing. "This seems to work."

I thank him for flying out from Provo. He thanks me for the ticket to the game and the 24 hours of nonstop entertainment. Then I go back to my place and sleep for sixteen hours.

Copyright © 2016 by J. Steven Young. Used by permission of Houghton Mifflin Harcourt. All rights reserved.