Former Puerto Rican boxing prospect Prichard Colón has died at the age of 33, nearly 11 years after suffering a severe brain injury that left him in a persistent vegetative state.

Colón’s death was announced on Thursday by his father and former coach, Richard Colón, in a Facebook post. He thanked those who had supported the family with prayers and encouragement over the years.

Colón was regarded as one of boxing’s promising young fighters and had compiled a 16-0 professional record, including 13 knockouts, before his career was cut short in October 2015.

The former junior middleweight suffered a brain bleed during his bout against American boxer Terrel Williams at EagleBank Arena in Fairfax, Virginia.

Colón was knocked down twice in the ninth round after receiving several blows to the back of the head, commonly known as rabbit punches. His corner subsequently stopped the fight.

He was taken to hospital and diagnosed with a subdural hematoma, requiring emergency surgery. He spent 221 days in a coma and never regained the ability to walk or speak.

Colón remained dependent on rehabilitation and family care for the rest of his life. His injury also prompted changes in boxing safety regulations.

In 2016, the World Boxing Council introduced the “Prichard Colón Rule”, which called for zero tolerance for blows to the back of the head.

Colón’s parents later filed a $50 million lawsuit against the ringside doctor and promoters involved in the 2015 bout.

Born in Maitland, Florida, on September 19, 1992, Colón won a gold medal at the 2010 Pan American Youth Championship before turning professional.