He was only 29 years old.

Lawal's first pro fight went down Sunday at the Harrow Leisure Centre in London ... where he faced Portuguese fighter Malam Varela (2-4).

During the 4th round of the Clash of the Titans undercard fight, Varela threw a right that landed directly on Lawal's temple, knocking him to the ground ... and the referee could tell Sherif needed immediate medical attention.

Ringside doctors and paramedics jumped into the ring and reportedly performed CPR on the canvas for over 10 minutes before he was taken to the Northwick Park Hospital.

Sadly, he didn't make it ... and was pronounced dead at the hospital.

Lawal's supporters were devastated by the news.

"I am so sorry to hear this. Such Talent," one fan wrote. "Condolences to Sherif's family & friends. May he rest in peace."

Sherif started boxing in 2018 and decided to go pro earlier this year ... a move supported by his boxing trainer, CJ Hussein.

"I think the pro game will suit Sherif down to a tee, he’s got all the talent to become a great middleweight," Hussein said to Camden New Journal.

"He’s a real inspiration to all the younger boxers at the gym."