But the Texas sophomore running back wasn't as blindsided by the prospect of a head injury potentially derailing his football career.
"It didn't really blindside me," Newton said. "I kind of had an idea, just from my previous history with (concussions)."
That history, and Newton's reaction to his most recent concussion, caused Newton to end his Texas career following a meeting with team doctors and his parents Saturday afternoon. Newton said the end decision was his choice, and came after "a lot of time for thinking and prayer."
Newton led Texas in rushing in 2009 as a redshirt freshman, and he finishes his career with 781 yards and nine touchdowns. Texas coach Mack Brown said that Newton would apply for a medical scholarship, meaning he won't count against Texas's 85-scholarship count.
Brown said Newton would continue to help out the program, working with the team's young running backs and potentially aiding his teammates in the academic tutoring center.
"He's sure earned his scholarship here," Brown said. "He's a great young man, he's up in the 3.0s as a student he's been very positive, the kids love him, he's been nothing but a great young man and leader on our football team."
Newton said he had suffered "a few" concussions, dating back to his time in high school. After each concussion, doctors take players through a battery of tests to see the concussion's effects.
At Texas, each player is tested upon arrival on campus to figure a "baseline" result against which to measure any potential concussions. The immediate aim is to help a player overcome the symptoms of his current concussion, but once that process is finished, Newton said doctors moved on to gauging future results.
"With concussions, a specific number isn't as important as how you recover from each one," Newton said. "I've had a few in the past, but it's not a set amount, where after you get a number of concussions, you can't play anymore."
Newton said his mother advised him to quit football after each concussion he suffered.
"That's just her being a mom," Newton said.
But his father told him that Newton needed to look at the facts that think about his future health.
"That's mainly what I was thinking about, right now," Newton said. "I wanted to get out there and play. But you have to think about the future. Because football is going to end one day.
"As much as I love football, and this is probably one of the hardest decisions in my life, football doesn't last forever," Newton said. "You have to think about your future and what's going to happen later on down the road."
Newton said he heard stories about players with head injuries, but said "you never think it will be you."
"When you're out there playing, getting hurt never crosses your mind," Newton said. "You think you're invincible out there. But it happens, and I'm going to have to deal with this."
Newton met with his parents and team doctors throughout last week before finally deciding his fate in a meeting at the football complex Saturday afternoon. He said his teammates told him they were behind him "100 percent." Newton is set to graduate next December with a degree in corporate communications. He has a 3.6 GPA, and is looking forward to applying to graduate school.
His loss will be felt on the Texas depth chart, both immediately and in the future. For now, it leaves the Longhorns with just one fully healthy back in Cody Johnson. Fozzy Whittaker is fighting a recurring stinger injury, and oversized H-back Chris Whaley and fullback Ryan Roberson have been getting repetitions at running back to pick up the slack.
Texas offensive coordinator Greg Davis said the staff wouldn't remove any redshirts this late in the season.
"(The decision) wasn't easy at all," Newton said. "Even today, I'm not thrilled or completely at rest with this, but I just know it's the right thing and it's better for me in the long run."