Controversial boxing legend Tony Ayala Jr. was found dead Tuesday at his San Antonio gym, close friends told local media outlets.

Ayala, 52, was found slumped over inside the Zarzamora Street Gym where he had been trained by his father Tony Ayala Sr. He had been trying to reopen the facility, KSAT.com reported.

No cause of death was immediately given.

Ayala Jr. was a former top contender for a world middleweight title before he was arrested for rape in New Jersey in 1983. He was convicted and served 16 years in prison before being released.

The former boxer violated his parole and was sent back to prison in 2004, where he served another 10 years.

Ayala was part of the Ayala boxing clan, which included his boxing father and three brothers who were both amateur and professional athletes, MySanAntonio.com reported.

"He was a very intelligent guy," Henry Rodriguez, a close friend of Ayala Jr., told MySanAntonio.com. "Some people would say too smart for his own good. He had good intentions here. He was certainly one of the greatest ever to come out of this city. He had a lot to offer."