Nigerian professional boxer Gabriel Oluwasegun Olanrewaju tragically passed away over the weekend ... after the light heavyweight fighter collapsed during an eight-round bout.

The Ghana Boxing Authority confirmed the death of the 13-8 boxer ... stating during the third round of the match, Olanrewaju fell back into the ropes without any contact from his opponent, 12-1 Ghanaian fighter Jon Mbanugu.

Referee Richard Amevi immediately stopped the fight when he realized something was wrong with Olanrewaju ... and the ringside physician and EMS administered aid, including CPR.

Olanrewaju was transported from the Bukom Boxing Arena to a local hospital where he died 30 minutes later.

"We are really devastated," said Remi Aboderin, the general secretary of the Nigeria Boxing Board of Control.

"[This] is not something we envisaged. We will live up to our responsibility and make sure that we stand [by] the family."

Olanrewaju was confirmed medically fit and approved to fight Mbanugu by the NBBC prior to the event.

Olanrewaju, a 6'1" orthodox fighter, began his pro boxing career in 2019 and won several fights, including the West African Boxing Union light heavyweight title after a knockout win over Simon Olayinka in 2023.

R.I.P.