Batyrgaziev clinched the title on split decision over fellow professional Ragan, whose defeat extends the United States' 17-year wait for an Olympic boxing gold medal.

Andre Ward, the last American to win gold in the sport at the Games when he claimed the light-heavyweight crown at Athens 2004, sent a message of encouragement to Ragan before the fight.

But Batyrgaziev proved too strong and was awarded the contest 3-2 after surviving a late onslaught from his American opponent.

"This has been my dream since I started training for boxing when I was a child," said Batyrgaziev.

"This has made all the hard work and effort and the discipline I've shown since worth it. 

"It has paid off.

"I am proud of my home. 

"It deserves to be the home of an Olympic champion and I’ll take the gold medal home to my people as I promised them."

Batyrgaziev looked the sharper of the two boxers in the opening round and was up on four of the judges' scorecards going into the final three minutes.

Ragan saved his best for the last round but it was not enough as Batyrgaziev held on for a narrow victory to earn the ROC team's first boxing gold of Tokyo 2020.

Professionals were controversially allowed to compete in the boxing tournament at Rio 2016, but only three did so and all performed poorly.

More than 40 professional boxers have entered the competition at Tokyo 2020, being organised by an International Olympic Committee Boxing Task Force after the International Boxing Association was stripped of its recognition because of severe issues with its governance, finances and refereeing and judging.

The final between Batyrgaziev and Ragan was the first boxing gold-medal bout ever contested by two professionals.

Batyrgaziev, a former kickboxer, has a 3-0 record as a professional, while Ragan has won all four of his pro fights to date.