Watch: Bernard Hopkins Knocked Out Of Ring By Joe Smith Jr. In Retirement Fight

Bernard Hopkins’ 28-year boxing career finished in defeat Saturday night as Joe Smith Jr. knocked the 51-year-old veteran out of the ring in the eighth round, ending the match shortly thereafter.

Watch: Bernard Hopkins Knocked Out Of Ring By Joe Smith Jr. In Retirement Fight

The bout was held at The Forum in Los Angeles and finished 53 seconds into the eighth round when Smith, 27, hit his much-older opponent with a six-punch combination that sent Hopkins through the ropes and onto the floor.

Referee Jack Reiss then called a halt to proceedings via a technical knockout after Hopkins failed to return to the ring after a period of 20 seconds.

Hopkins cited a blow to his head, as well as a twisted ankle as a reason for the TKO that prohibited him from re-entering the ring.

“I’m really still in shock,” said Hopkins. “This is my last fight, I promised it would be and you come to that point in life where it is final and I’m happy with my retirement.

“I know the fans will know I went out as a soldier, fighting the toughest, baddest opponents. I’m not saying I agree, I’m not in denial Joe was a tough, heavy hitting fighter.”

Hopkins, who was known as ‘The Executioner’ throughout his career, ended with a professional boxing record of 55-8-2, which included 32 knockouts.

In 2013, he became the oldest boxer in history at 48 to win a major title with is IBF light heavyweight victory over Tavoris Cloud.

One year later, Hopkins beat Kazakh boxer Beibut Shumenov by split decision to become the oldest boxer to ever unify world titles, earning the WBA ‘Super’ light heavyweight title. Saturday’s fight marked his first since a crushing defeat to Sergey Kovalev in November 2014.

Smith, meanwhile, has improved his record to 23-1, including 19 knockouts, and praised Hopkins following the bout.

“I knew he was a true champion, and if he didn’t get injured he’d be back here,” said Smith. “I had seen him fall, and I kept hitting him until I saw him go out, and I landed that left hook until he went out.”

Smith continued: “I knew he had time to go out, but I hit him with four or five clean shots and they were good shots on the button. I came here to do my job. This is my coming out party, too. I had to finish him. It was either my career was going to end and his was going to end, but I needed mine to continue.”

INGLEWOOD, CA – DECEMBER 17: Bernard Hopkins punches Joe Smith Jr. as Smith goes on to win the WBC International Light Heavyweight title in a ninth round TKO at The Forum on December 17, 2016 in Inglewood, California. (Photo by Harry How/Getty Images)