Vasyl Lomachenko stopped WBO super-featherweight champion Rocky Martinez to become a two-weight world champion on Saturday night in New York's Madison Square Garden.
The brutal fifth-round knockout saw Lomachenko make history by becoming the first boxer to win a second world title in a different weight class in just his seventh fight.
Lomachenko, who won the WBO featherweight title in his third fight, dominated the Puerto Rican with vicious left-handed leads and connected with four straight, including a precise uppercut in the fifth round.
The Ukrainian double Olympic champion followed up with a stunning right to leave Martinez motionless on the canvas for several moments.
"I came to do my job, I did my job very well tonight," said Lomachenko before dedicating the win to "the greatest man who ever laced up gloves, Muhammad Ali."
Lomachenko, a three-time world amateur champion, celebrated victory with a backflip in the centre of the ring afterwards and promoter Bob Arum tipped the 2008 and 2012 gold medallist as star of the future.
"I think anybody who follows boxing would see this performance and realize they have seen the birth of a superstar," said Arum.
Martinez, who was making the second defence of his title, admitted he was caught out by the speed of the 28-year-old.
"I couldn't see his hands," admitted the 33-year-old Martinez.