Gabriel James Gamez, 24, is accused in the death of 18-year-old Darrell Turner.
Prosecutors say Gamez opened fire on teammates from Gateway High School in Monroeville, Pa. The players and their team had stopped in Durham en route to a Florida football camp in June 2011.
Gamez also faces an assault charge after another player was shot in the leg.
The attorney for Gamez said in closing arguments that her client felt threatened by the players and was scared for his life. A prosecutor said Gamez was the aggressor and that the football players did nothing wrong.
Jurors failed to reach a verdict Wednesday. They will return to deliberate at 9:30 a.m. Thursday.