Promising super middleweight prospect Darren Sutherland, who won an Olympic bronze medal for Ireland at the 2008 Games in Beijing, was found dead Monday at his London home, according to manager Frank Maloney.
Sutherland was 27.
According to British media reports, Sutherland was found hanged.
Maloney, who found the boxer's body, said in a statement that his death was "very sad and unexpected. At this sad time my thoughts are with Darren's family and I hope their privacy at this very difficult time will be respected by the media. It is a tragedy for Ireland and the world of boxing."
Maloney was taken to the hospital suffering from shock after finding Sutherland. Tests revealed that the 55-year-old manager had a heart attack, but it was not clear if the attack happened before Monday's events. He is expected to remain in the hospital a few days, and doctors are allowing him to work on his laptop.
Sutherland advanced to the semifinals in the Olympics before losing to eventual gold medalist James DeGale of England.
Sutherland made his professional debut on Dec. 18, scoring a first-round knockout of Georgi Iliev in Dublin. He had advanced to 4-0 with four knockouts, his last bout a fourth-round knockout of Gennadiy Rasalev on June 30.
Sutherland's next fight had been scheduled for Oct. 16 in England.
DeGale paid tribute to his former rival.
"He had an Olympic bronze medal and his whole life to look forward to," the Englishman said. "He had a great future and my heart goes out to everyone who knew him."
Former world featherweight champion Barry McGuigan, who was born in Ireland, said Sutherland had the ability to win a world title.
"I am deeply shocked and deeply saddened by this news and my heart goes out to Darren's family," McGuigan said Tuesday. "It is an absolute tragedy. I would describe Darren as a phenomenal talent.
"He represented his country with pride as an amateur and I believe he would have become a world champion in the professional ranks one day."
Maloney, a former manager of world heavyweight champion Lennox Lewis, remained in the hospital but doctors were allowing him to work on his laptop. He is expected to remain there for a few days.
Dan Rafael is the boxing writer for ESPN.com. Information from The Associated Press was used in this report.