A renowned boxing magazine 'Ring Magazine' have now reported the 28-year-old has also succumbed to injuries.
Urakawa’s death comes just a day after fellow boxer Shigetoshi Kotari also died of injuries sustained during the card.
The super-featherweight was taken to hospital following the fight in Tokyo, where he had emergency brain surgery to treat a subdural hematoma - a condition where blood collects between the skull and the brain.
Following the death of Kotari, the World Boxing Council announced an immediate change to its rules.
WBC president Mauricio Sulaiman said, "Deeply sorry for this loss, a ring accident which makes all of us go back to continue research to find ways to make boxing safer and implement prevention programmes.
"Our deepest sympathy and condolences for his family and the boxing community in Japan."
Following the August 2 event, the Japan Boxing Commission announced all Oriental and Pacific Boxing Federation (OPBF) title bouts will now be 10 rounds instead of 12.
Kotari fought to a draw with Hata for the OPBF super-featherweight title, while Urakawa was knocked out by Saito in their featherweight bout, according to a BBC news.
