He redshirted his freshman season at Troy and entered spring practices after spending countless hours working on his strength and flexibility.
His coaches noticed a change in his body, now 6-foot-9 345-pounds, but also noticed the time spent trying to become more flexible in his hips wasn't yielding any progress.
"I'd worked so hard to get more flexible. I can't tell you how much time and effort I put in," Banner told FOX Sports SCPlaybook, noting he even took up yoga.
Upon coaches suggestions, Banner saw a few doctors in the spring and all came back with the same opinion. He is suffering from a condition he's had since childhood known as Femoroacetabular Impingement or FAI, which has directly affected the flexbility in his hips.
It's a hip impingement that causes his bones to rub against each other.
Banner said he was "devastated" at the news, learning that he could suffer from arthritis by age 30 if the condition wasn't surgically corrected.
Banner admitted he "broke down", but soon realized once the condition is corrected he'll be able to have full range of flexibility in his hips.
After learning of his diagnosis in the spring, Banner spoke with now former head coach Lane Kiffin and offensive line coach Mike Summers about the doctors' findings.
With his parents and coaches, Banner decided to play through the 2013 season, thinking he could withstand the pain he'd already been living with his entire life.
"All the doctors said as long as there was no abnormal pain that I could just get the surgery at the end of the season," he explained.
However, after the game against Boston College, Banner says the pain became unbearable in his hips, barely able to get into his stance on the offensive line during warmups.
"I was trying so hard to bend," he said. "But I just couldn't."
It was then, with his parents, that Banner decided the only option was to have the surgery immediately in order to relieve the building pain and prevent micro fractures in the bones.
"I want to be out there with my teammates more than anything," he said. "It killed me to watch the Arizona State game happen. But I can't do anything."
He'll have surgery, which involves shaving his bone, on one hip this coming Friday. The following hip will undergo the same procedure four weeks later.
Banner is expected to make a full recovery. In fact, he'll be better than before, with a full range of motion in his hips that he's never experience before.
The timeline to return to 100% is expected to take six to eight months. He says he has no doubt he'll be ready when 2014 fall camp opens.
"Getting this done," he said, "it will absolutely make me a better player. I'll finally be able to bend the way I'm supposed to in order to be a tackle."
According to Banner, he will not be granted a medical redshirt and will have three years of eligibility remaining.