It is unknown when the tear occurred, but the coaching staff began to notice a difference in Yates' throwing ability towards the end of the season.
"We started talking to T.J. with about three to four games left in the season, and actually asking him if was fatigued," Davis said. "There was a little bit of lack of velocity with the ball in practice, so [offensive coordinator] John Shoop cut back his reps and starting sharing those reps between Cam [Sexton] and Mike Paulus during practice time…
"And then on game days, you would just see little tiny bits of evidence on certain throws that you would go, ‘I wonder if his arm is tired?' And it may have, in fact, not been a tired shoulder because we kept asking him and he'd say, ‘No, I'm okay. There's no real pain. I'm not hurting.'"
Davis indicated that there is even a possibility that the injury may have occurred in high school.
Yates' estimated recovery time will not be known until after the surgery is performed.
"The expectations are that he'll be 100 percent and he'll come back and he'll be fine," Davis said.
The Marietta, Ga. native played just two years of high school football -- and only one in a passing offense -- prior to coming to North Carolina.
Yates started all 12 games for North Carolina this past season, after winning the job in fall practice. He completed 218-of-365 attempts and set the UNC single-season passing yards record with 2,655. Yates also had 14 passing touchdowns, which ranks second on the UNC single-season list, and had two rushing scores.
He finished second in the voting for both the ACC Rookie of the Year and ACC Offensive Rookie of the Year awards and was named to The Sporting News All-ACC Freshman Team.