Australia's George Kambosos used a high-energy attack and a stinging overhand right to become the unified lightweight boxing champion with a shocking split decision victory over Teofimo Lopez on Saturday night in New York.

Both boxers came into the fight undefeated but the heavy underdog Kambosos made sure he was the one to leave with the 135-pound straps.

The 28-year-old Kambosos snatched the WBA, IBF and WBO belts in a close slugfest at the Hulu Theater at Madison Square Garden that left the fighters bloodied and bruised by the end of the 12th round.

He had to bounce back from a 10th round knockdown to earn his third split decision victory in a row.

"I wasn't hurt," said Kambosos of the knockdown. "I said to my corner 'Let's go hard. I am going to punish this kid.'"

Kambosos won by 115-111 and 115-112 on two judges' scorecards to improve to 20-0, with 10 KOs. One judge gave the fight to Lopez 114-113.

The American-Honduran Lopez was coming off a career-long 13-month layoff for a fight that was a year in the making.

The soap-opera buildup to the showdown included eight postponements, six proposed locations and numerous legal challenges because of in-fighting between boxers, promoters followed by lawsuits.

There were fireworks from the opening bell as Kambosos, who was a 13-1 underdog, knocked Lopez down in the first round.

The pair both landed several hard rights in the round, but Lopez got caught with a looping overhand right to the temple. Kambosos would go back to that punch over and over with great success throughout the fight.

In the 10th, Lopez knocked Kambosos down with a chopping right hand of his own halfway through the round.

Lopez suffered a bad cut over his left eye in the 11th and the fight was stopped briefly so the ring doctor could take a look at it. The fight continued into the 12th as Lopez's corner was unable to stop the bleeding between rounds.

Lopez interrupted Kambosos' post-match television interview to say he was robbed and only lost two of the 12 rounds. Kambosos responded by saying "you are delusional."

"I won tonight," Lopez said as the crowd booed. "The ref didn't raise my hand. I am not a sore loser. I came out here and did what I had to do. I won 10 of 12 rounds."

The previously unbeaten Lopez was fighting for the first time since his breakthrough win over Vasiliy Lomachenko in October 2020 in Las Vegas.

The win elevated Lopez to the rank of undisputed champion but instead of capitalizing on his success, he lost all the titles in just his first defence attempt.

He was initially scheduled to fight Kambosos at the end of May but a series of postponements followed, including one because Lopez contracted Covid-19.

Lopez announced he had Covid-19 days after attending the June 12 Shakur Stevenson-Jeremiah Nakathila fight in New Jersey.

Skilled boxer

The New York-born Lopez represented Honduras at the 2016 Summer Olympics in Rio de Janeiro but failed to win a medal. He is now 16-1 with 12 knockouts as a pro.

Kambosos, who lives in Sydney, showed that not only is he a skilled boxer -- but he can take a punch.

Kambosos also posted split decision wins over Mickey Bey and Lee Selby in his previous two fights. The Selby fight took place in October of last year, meaning the Aussie had also been out of the ring for 13 months.

This was just Kambosos' third fight in the United States.

On the undercard, Japan's Kenichi Ogawa captured the vacant IBF junior featherweight title by beating a bloodied Azinga Fuzile in 12 rounds.