Financial cuts made it harder to maintain the gym, which closed in 2006 after vandals had ripped out wiring and copper pipes, cutting off water service.

While some of the boxing community had plans to maintain it through private funding, this never became a reality, but the training program was relocated to another part of the city.

Detroit deputy fire commissioner David Fornell told the Detroit Free Press: “We tried to attack it from inside but because of the danger of the roof falling in, the chief pulled the crew out and [we] fought the fire from the outside.”

The roof caved in but the crew fought the blaze for over four hours.

Fornell does not think there is any connection between the fire and a recent one at the auditorium at the disused Cooley High School building nearby.

Hearns, also known as “The Hitman”, was named Fighter of the Year by The Ring magazine in 1980 and 1984 – the latter following his one-punch knockout of Roberto Durán.

He was known as a devastating puncher throughout his career, even at cruiserweight, despite having climbed up five weight classes.

By Declan McSweeney