As a sophomore, he played in 10 games and made eight tackles, including one against Florida State.
Bunting moved him to the starting strong side linebacker position at the start of summer training camp in August. Alongside senior middle linebacker Quincy Monk and senior Merceda Perry on the weak side, Thornton was the only player in the front seven without significant game experience.
"That was an adjustment for David to make in training camp, and he did a tremendous job," Bunting said. "He didn't start fast, but he finished strong."
Start slow and finish strong could just be Thornton's mantra. When he tried out as a 170-pound freshman, now-Texas coach Mack Brown still reigned at North Carolina.
When Thornton and place-kicker Chris Bender, defensive tackle Anthony Perkins, and place-kicker Jeff Reed walked on to Brown's team, tryouts consisted of heavy conditioning, including what Thornton called a "survival run."
"If you made it through that, they pretty much kept you," Thornton said.
"You were used as a scout player, which I didn't mind. I just wanted to play with the team and be a part of Carolina football."
Thornton moved on to play in 10 games his sophomore season as a special teams contributor.
He continued on special teams during his junior season, but former North Carolina coach Carl Torbush told him that he would have to be more consistent to earn a scholarship.
This didn't bother Thornton in the least.
He persevered, and at the close of the 2000 season, Torbush promised Thornton a scholarship, and Bunting followed through when he took the helm, granting Thornton the award in the spring.
"I wasn't expecting it at all," said Thornton, who is now pursuing a master's degree in sports administration. "I had heard through the grapevine that I had a chance of possibly getting a scholarship, but that was never in my intentions for playing football. I just wanted to play hard."
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After gaining his scholarship, Thornton had another challenge to face. In order to play at the linebacker position, he had to gain weight. He sat down with Jeff Connors, the Tar Heels' strength and conditioning director, to figure out a diet.
By the end of the summer, Thornton had gained 15 pounds, and in UNC's first game he proved he could play against the nation's best -- something he didn't think was possible when he first tried out as a freshman.
"At first I didn't think I could do it," Thornton said. "But from the time I got out there and saw that these guys put on their pants the same way I do, they perform and work hard just like I do, so I felt like maybe I have a chance to compete, and maybe one day I'll be able to play on Saturday.
"I definitely just want to work hard and see how far I can let this thing ride."
The Sports Editor can be reached at sports@unc.edu.