Francisco Vargas went down in Round 4 and seemed to be on the verge of a loss at the end of Round 8 in what was already a classic slugfest. But then the man from Mexico staged a remarkable comeback and pummeled incumbent WBC junior lightweight titleholder Takashi Miura into submission to end the back-and-forth battle at Mandalay Bay in Las Vegas on Saturday.

Referee Tony Weeks stepped in at 1:31 of Round 9 after Miura was knocked down and attempted to hang on but absorbed a series of flush power shots with no response.

It was the lead-in bout to the main event pitting RING middleweight champion Miguel Cotto against Canelo Alvarez.

With the win, his 20th in a row, Vargas moved his record to 23-0-1 (17 knockouts) while Miura fell to 29-3-2 (22 KOs).

A full report from Doug Fischer will follow.