A 29-year-old British fighter died after he collapsed in the ring during his professional boxing debut on Sunday night in the U.K. Rising middleweight Sherif Lawal took a shot from Portuguese fighter Malam Varelan in the fourth round of a bout at the Harrow Leisure Centre in Greater London. The fighter was treated by paramedics at the scene and rushed to a hospital, the BBC reported, but he did not survive his injuries. ESPN cited media reports that Lawal took a shot to the temple before he went down and never got back up. No cause of death was immediately available. The British Boxing Board o…