Former double world champion Takahiro Ao will enter the ring for the vacant WBO lightweight belt against Mexico's Ray Beltran on May 1 — the eve of the Floyd Mayweather Jr.-Manny Pacquiao megafight — at the Cosmopolitan of Las Vegas.

"I'm excited," said Ao, a former champion in the WBC featherweight and super featherweight divisions, at a news conference at Teiken Gym on Thursday. "And a big feat to be world champion in three different weight classes will be at stake, so I'm already psyched up."

Ao, who will turn 31 next week, earned the nod for the title shot by defeating former super featherweight champion Juan Carlos Salgado in a unanimous decision last October.