Two judges scored it 48-46 for Edwards, while the third judge had it at 47-47.
Edwards is unbeaten in 12 consecutive fights and has not lost since Usman defeated him via unanimous decision in their first fight in 2015.
Usman won 15 consecutive fights in the UFC before losing his past two to Edwards.
It was the third meeting between Usman and Edwards, who was less than a minute from sure defeat in their last meeting when he Pulled off a shocking head-kick knockout to finish Usman at UFC 278.
Edwards established himself in the first with hard kicks to the body and legs, but Usman got going in Round 2, taking Edwards to the mat and landing some hard shots on the ground.
Usman struck first in the third round, working a single leg before scoring a takedown in the first minute. Edwards managed to get to his feet and moved toward the cage, but referee Herb Dean penalised Edwards a point for grabbing the fence as Usman took his back.
Similarly, Jones knocked our Gane to take possession of UFC heavyweight pinnacle_ Jones Knocks out Gane to take possession of UFC heavyweight pinnacle
