That was when Quinn stepped off a curb and rolled his ankle, fracturing a bone and straining tendons in his left foot.
The injury forced him to miss two meets, but Quinn returned to competition Sunday as North Carolina hosted Clemson in Chapel Hill. It was his first meet since Nov. 3.
"It was really stupid," Quinn said of the injury.
It was also frightening for his teammates and coach Frank Comfort, who described Quinn as one of the team's best athletes and competitors.
"Sean's our superstar," said sophomore Yuri Suguiyama. "He brings a level of confidence to the team."
Quinn's confidence was missed in both a meet against Duke and the Nike Cup. But a long rest during the winter break allowed him to rehabilitate the foot and return to the pool faster than expected.
In his first meet back, Quinn won the men's 200-yard breaststroke, touching first in 2 minutes, 1.56 seconds. He also finished third in the 100 breaststroke and fourth in the 200 individual medley relay.
Quinn was disappointed with the latter two finishes, especially since the No. 17 Tar Heel men lost to the unranked Tigers.
"I blame myself first," Quinn said. "In the breaststroke, I got third place, which is inexcusable."