Coulibaly, who went scoreless in the team's opener against Cameroon, came up big, propelling the Malian offense with 11 points.
It was his first eye-catching performance for his country since he last represented Mali at AfroBasket 2011.
Lerry Essono Mve, the most dynamic in the Gabonese side, finished with a team-high 11 points, but Gabon were unable to avoid their second defeat in the tournament.
Stats Don't Lie: Even though Mali turned the ball over a tournament-high 29 times, Gabon's poor field-goal shooting (31 percent) didn't help their aspirations in the contest.
Game Hero: Boubacar Moungoro came off the bench and shot 3-of-5 from three-point range for a game-high 13 points.
The Bottom Line: In their first meeting since 2005, Mali came out stronger and improved their chances in Group C, while Gabon displayed some worrying struggles at both ends of the floor. Obviously there is still one more game for Gabon in the Group Phase, but having only one player to score in double digits for the first time in the tournament is concerning. It is even worrying to sharing the ball below eight assists for the second game in a row, which says a lot about Gabon’s position in the tournament.