Patrick Day has succumbed to a traumatic brain injury, the boxer's family announced.

Day was knocked out during the 10th round of his USBA super welterweight title fight with Charles Cornwell on Saturday in Chicago. He was only 27.

Charles Cornwell, a 2016 US Olympian for boxing, struck him behind the ear that caused him to hit the canvass. USA Today and Sports Illustrated reported how the match ended, with Day being stretchered off and rushed out of the ring.

He was knocked down twice before that fatal punch on the 10th round. Day was immediately rushed to Northwestern Memorial Hospital in an ambulance where he was reported to be in critical condition.

His management company DiBella released a statement on Sunday, saying that Patrick Day was in a medically induced coma to help his brain recover from the injury.

DiBella Entertainment announced on Wednesday of his passing. In a statement, they said that Patrick Day died due to a traumatic brain injury he suffered from the fight he had on Saturday. During his final moments, he was surrounded by family and a few close friends. His mentor and friend Joe Higgins, along with his boxing team, was also there.

Before his untimely demise, Day was a celebrated professional boxer. Prior to entering the circle of boxing pros, he won two national boxing titles. He also won several matches in the New York Golden Gloves tournament and became an alternate in 2012 for the US Olympic boxing team.

In 2013, Patrick day became a pro and earned his spot as a world-rated contender for the super welterweight division.

In 2017, he won the WBC Continental Americas championship and another award from the International Boxing Federation early this year.

In addition to pursuing his career in professional boxing, Day was also inclined to pursue further education, preparing for a good future for him and his family.

Patrick Day may be a world-renowned professional boxer. However, to his family and friends, he will always be remembered as the son, the brother and a good friend. His kindness, positivity, and generosity of good spirits left a lasting impression on everyone he has met and worked with.

Following what transpired during Saturday's fight, Cromwell, 21, wrote an open letter. He expressed his deepest sympathies over what happened. He shared that he never intended for any of this to happen to Day.

He also said that he never wished this to happen to anyone and emphasized that if he had the chance to take it all back, he would.

Cromwell offered his sincere prayers to Patrick Day and to the loved ones he left behind. He went on saying that he will continue to pursue boxing because he believes that Day would be doing the same thing. He said he will use Day as an inspiration to leave the ring alive and well every time.

Prayers and sympathy are sent to the bereaved family of the boxer.