Mexican Jaime Munguia retained his WBO junior middleweight title with a unanimous decision win over Liam Smith on Saturday night.
The 21-year-old Munguia improved to 30-0 with 25 knockouts by becoming just the second boxer - along with Saul 'Canelo' Alvarez - to beat Smith.
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While Munguia did not knock Smith out, he easily won the 154-pound fight by scores of 116-111, 119-110 and 119-108.
With about 40 seconds left in the sixth round, Munguia landed a left hook to the side of the head that knocked Smith down. He hurt him again three rounds later with a hook to the body.
"I did very well, it was a tough fight," said Munguia following the first defence of his title. "I was looking for the knockout. I went to get the knockout and I always put my heart into the fight like a true Mexican."
Former world champion Smith dropped to 26-2-1 overall as the Liverpool native failed to recapture the title he lost to Alvarez in 2016.
Smith, who was making his Las Vegas debut, captured the crown in 2015 with a seventh-round stoppage of John Thompson.
While he was overmatched on Saturday he still fought to the end and even managed to land the final punch of the fight in front of a crowd of 2,400 at the Hard Rock Casino in Las Vegas.
"He was a tough opponent," Munguia said of Smith. "We went to the decision, no problem, it is a learning experience."
On the undercard, junior lightweight world titlist Alberto Machado easily beat challenger Rafael Mensah, winning 120-107 on all three scorecards.
Watch Dillian Whyte vs Joseph Parker with Katie Taylor, Dereck Chisora, Joshua Buatsi and Conor Benn all on the undercard, live on Sky Sports Box Office, from The O2, Saturday, July 28.