Tragic news ... South African boxer Simiso Buthelezi -- who became disoriented during a fight over the weekend and began punching thin air -- has died.
Boxing South Africa confirmed the awful news Wednesday morning -- saying Buthelezi passed away on Tuesday night at a hospital in Durban.
He was just 24 years old.
Buthelezi had been initially hospitalized on Sunday following a terrifying scene in a boxing tournament in Greyville, Durban.
Very scary in South Africa please 🙏🏼 for Simiso Buthelezi (4-1). At 2:43 of the 10th & final round, Siphesihle Mntungwa (7-1-2) falls through the ropes but then Buthelezi appears to lose his understanding of the present situation. Mntungwa takes the WBF African lightweight title pic.twitter.com/YhfCI623LB
Video from the fight showed Buthelezi, in the 10th round of the bout against Siphesihle Mntungwa, advanced to a corner of the ring following a brief break in the action ... and threw punches at air -- seemingly fighting an invisible man.
He later collapsed in the ring ... and was rushed to the hospital, where -- according to Boxing South Africa -- it was discovered he had a brain injury and was internally bleeding.
"At the hospital," Boxing South Africa officials said in a statement, "Mr. Buthelezi was given the best care possible but he however succumbed to the injury last night."
It's unclear when, where and how Buthelezi suffered the injury -- he was reportedly in control of the bout from the opening bell.
Boxing South Africa said in its statement an investigation into the fight and the death is underway.
"The Buthelezi family and Boxing South Africa acknowledges warm words of condolences of the Minister of Sport, Arts and Culture," officials said.
Buthelezi had been unbeaten in the ring prior to Sunday's fight.