Day, 27, had been in a coma for four days following his defeat and, despite having emergency brain surgery at Northwestern Memorial Hospital, doctors were unable to save the junior middleweight.
Vikas, who has signed up with the legendary Bob Arum's Top Rank Promotions, made his debut in what was to be a six-round super welterweight contest. The bout, however, lasted just two rounds.
Summary of sports events and persons who made news on Friday