NASCAR and Charlotte Motor Speedway enlisted input from several Sprint Cup drivers in their latest format for the Sprint All-Star Race, scheduled for May 21.
The result, announced on Friday, is a 113-lap race that features two 50-lap segments, each requiring a green-flag pit stop to change a minimum of two tires, and a closing 13-lap shootout that counts only green-flag laps.
A drawing before the final segment will determine whether the top nine, 10 or 11 cars will be required to come to pit road and change tires for the last run. Those cars with fresh rubber will line up behind the remaining cars, which must stay on track on old tires, which must have been changed in the second segment before Lap 85.