Saul Alvarez beat Miguel Cotto by a unanimous points decision to claim the WBC middleweight title in Las Vegas.
The 25-year-old Mexican was too powerful for his 34-year-old Puerto Rican opponent, winning 119-109, 118-110 and 117-111 on the judges' cards.
"I'm very happy," said Alvarez. "Much respect to Miguel Cotto. He's a great champion. But now it's my era."
Alvarez, who has won 46 of his 48 professional fights, now wants to face unbeaten Kazakh Gennady Golovkin.
"If he wants to fight right now, I'll put on the gloves and fight him right now," said Alvarez.
WBA and IBF champion Golovkin, 33, has 31 knockouts from his 34 career wins.
On the undercard, Francisco Vargas recovered from the first knockdown of his career to win the WBC super-featherweight title with victory over Takashi Miura.
Despite nasty cuts above and below his right eye, Mexican Vargas stopped his Japanese opponent in the ninth round to end a brutal fight.
Vargas, 30, is unbeaten in 23 fights, while defeat was Miura's second in his 34 bouts.