AUSTIN, Texas -- There's a story behind the skin below Case McCoy's left eye, one he usually doesn't spend much time telling. He didn't know what to say when he was younger. People asked if it was a burn or scar. He'd just call it his birthmark.

He feels no shame about the stretched, discolored skin that marks portions above and below his cheek. Those blemishes are what remain from his eight-year, childhood battle with a rare autoimmune disease.

They serve as his daily reminder to keep battling.

"Every time I look in the mirror and see it, I know what I'm doing. I know why I'm fighting the way I am and what I'm fighting for," McCoy said. "I knew as a young boy that those marks aren't going away. It is who I am and I can either embrace them or be embarrassed by it."

All his hard work has led to this. Texas' self-assured senior quarterback is finally getting his moment. He's won three straight games to begin Big 12 play and is playing the best ball of his life. This is his team now.

He's injected much-needed swagger into these Longhorns, but where does that come from? The source of McCoy's moxie isn't found in a 3,000-seat high school stadium in Graham, Texas, nor the Cotton Bowl, where he beat Oklahoma two weeks ago in the finest game of his career.

The story of how Case found his confidence takes place in a hospital.

The first sign wasn't found on his face. It started with a spot near his left ankle.

A spot dark enough that Debra McCoy just assumed her 4-year-old son had dirt on his foot. She tried scrubbing it off. Nope, not dirt. Case took off his shirt. More spots, on the left side of his back. They continued to develop on his face and arm. His family had no idea why.

"As a mom, little red flags were going up," Debra said.

The marks under Case McCoy's left eye are reminders of his eight-year battle with scleroderma. AP Photo/Eric Gay

The family sought answers from physicians and specialists. A biopsy performed by a dermatologist produced the reason for the spots: Case was suffering from a form of scleroderma, a disease that involves the hardening of skin and the tightening of connective tissues.

The type of scleroderma he was facing, morphea, is usually found in adults age 20 to 50. Not pediatric patients.

"There was so much fear and so much anxiety," Debra said, "and we had these three healthy kids, and then overnight, Case went from healthy to not-so-healthy. ... You have a 5-year-old that gets himself out of bed and he's walking around like an 85-year-old arthritic man."

Soon after the diagnosis, McCoy and his parents began traveling regularly from West Texas to visit Texas Scottish Rite Hospital for Children in Dallas. The first two rounds of treatment he tried didn't slow the disease, and the side effects were brutal. He was shedding weight, wouldn't eat and started losing his hair.

"I started to realize, OK, this is pretty serious," Case said.

So doctors tried methotrexate, a drug used to treat rheumatoid arthritis. The results were promising. The process was excruciating.

Every Wednesday night after church, Brad McCoy had to give his son the shot. And every time, the boy ran right to the bathroom and puked. Many times, Brad said, Case would get violently sick and nauseous for more than 30 minutes.

"Wednesdays are not my favorite day," Case said. "I don't know why. I can only blame it on this."

His father set a standard from the very beginning: No excuses. Case got up on Thursday and went to school. Rarely did he ask if they could skip the week's shot or wait until the morning. The answer was never yes.

The treatments continued for nearly eight years. Once a month, the McCoys drove back to Scottish Rite. Older brothers Colt and Chance joined them on every trip.