LAS VEGAS — Baltimore boxer Gervonta Davis missed his weight Friday, forcing the fighter to forfeit his world title on the eve of the biggest bout of his young career.

Davis, 22, weighed in at 132 pounds, two pounds too heavy to enter the ring with his belt and defend the IBF championship he won seven months ago. He’ll still fight Francisco Fonseca on the undercard of Saturday’s show featuring Floyd Mayweather Jr. and Conor McGregor.

Davis, hand-picked by Mayweather to be the sport’s next superstar, quickly tweeted an apology to fans on Friday afternoon.

“I’m young, I’m growing. I had a chance to make the weight I knew I couldn’t make it & that’s that,” he said. “I will have a belt again.”

Davis (18-0, seven KOs) won the IBF’s junior lightweight title with a seventh-round knockout of José Pedraza in January. Saturday was to be his second title defense, but he needed to weigh in at between 126 and 130.

Fonseca (19-0-1, 13 KOs) weighed in at exactly 130 and will now have an opportunity to win the suddenly vacant title on Saturday night. Even if Davis wins the bout, the title will remain vacant.

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