Fisher was the first to arrive at the scene of a Brentwood, Tenn., car crash in which a Nissan Altima skirted off the road and overturned after hitting a pole, according to WKRN-TV.
Authorities told the TV station that after the 17-year-old driver lost control of the vehicle, a 13-year-old passenger was thrown from the car.
Fisher encountered the scene on his way home.
The coach told WKRN he stayed with the victims and attempted to provide aid until medical help arrived. Fisher then departed without taking credit for his good deed.
"I got there after, I saw him, we were going to our cars, (but I) didn't speak to him," Brentwood vice mayor Rod Freeman said of Fisher. "If he stopped and helped, that is fantastic, and I appreciate it."
The 17-year-old driver was treated at a nearby hospital and released, according to the TV station. The 13-year-old was listed in critical but stable condition at Vanderbilt Children's Hospital.