But not to his two best friends from Putnam City North High School, Ben Bench and Connor Boyd.
"We all knew how good he was going to be,” said Bench, a golfer at Oklahoma City University. "He's so good at everything. That's how those athletes are, so much better than anyone else. I knew he was going to be something special.”
Bradford has been something special.
He broke the NCAA freshman record for touchdown passes in a season with 34.
Bradford also heads into the bowl season leading the nation in passing efficiency.
"I'm not surprised, not at all,” said Boyd, who played wide receiver for Putnam City North. "I knew since little league he would be a phenomenal athlete. I'm not fast or quick, but I caught a lot of balls because Sam put it on the money every time.”
Bradford, Bench and Boyd spent most of their childhood competing in anything from ice hockey to golf.
"We played just about everything,” Bradford said. "We'd get a 21 game going or 2-on-2 football or hockey. We'd play whatever we felt like at the time.”
One morning, the trio elected to play 112 holes of golf at Mustang's Pebble Creek golf course, which is exclusively comprised of par 3s.
"Mom dropped us off before she went to school at 7,” Bradford said. "And dad picked us up that evening at 9.”
Boyd, the non-golfer of the three, connected on a hole-in-one, drawing the envy of the other two.
"I remember I didn't think it should've counted because it came on the front tees,” Bench said. "I was probably a little jealous that the non-golfer of the group did it. And Sam was giving me a hard time, too, asking me why I hadn't gotten a hole-in-one — I was getting annoyed.”
The trio still hangs out often, sometimes getting together at Bradford's house after an OU home football game to play ping-pong.
Two weeks ago, they watched Floyd Mayweather score a 10th-round technical knockout of Ricky Hatton.
But Bench and Boyd admit that all isn't the same.
"Anywhere we go in public, everyone knows who he is,” Bench said. "People constantly are coming up to us, asking for an autograph or a picture.
"It's amazing how much a life can change.”
But while Bradford's fame quickly grows, his friends say he is the same person he was in high school.”
"He's the most humble guy I know,” Boyd said. "He never talks about himself unless you bring it up, never brags.
"He's still the same — just real down to earth.”