Angel Ayala and Dave Apolinario are set to fill the void left behind by one of the sport's very best.

Both fighters arrived in supreme condition ahead of their vacant IBF flyweight title fight in Mexico City. The locally-based Ayala arrived at a fit and trim 110.8 pounds, while the Philippines' Apolinario was a fight-ready 111.7 pounds.

Their bout headlines an ESPN Knockout show from Restaurante Arroyo in Mexico City. ESPN+ will stream the event live in the U.S.

Ayala (17-0, 7 KOs),No. 4 at 112, enters his first career title fight as the mandatory challenger. He earned that right after a questionable 12-round win over Felix Alvarado last October 14 in Merida, Mexico.

"With this fight, I can now become a part of boxing history,"

There was always the realization among Ayala's team that his bid for the IBF belt would come in a vacant title fight. Jesse 'Bam' Rodriguez (20-0, 13 KOs) previously held the IBF and WBO titles at flyweight but vacated both belts earlier this year.The Ring's No. 5-rated pound-for-pound fighterreturned to 115, where he dethroned long-reigningRING champJuan Francisco Estrada.

Apolinario (20-0, 14 KOs) was the benefactor from the move, as the No. 3-rated IBF contender. The unbeaten contender from General Santos City gains his first title fight through attrition rather than merit. His resume is fairly thin, although three of his last four wins came on the road. He enters on the heels a fourth-round stoppage of Tanes Ongjunta on February 22 in Tokyo.

"This fight is a big difference from any other I've had and I'm excited to prove I'm the best," Apolinario said. "I had a long time to prepare for this. This fight is very important and I have improved my skills, my power... and also my IQ."

Both fighters were required to wait out a purse bid process, which killed plans to land on theMay 6 Naoya Inoue-Luis Nery card in Tokyo.Zanfer Boxing, Ayala's promoter, bid $250,500 to to secure promotional rights.

Friday's fight date satisfies the terms of the bid, which called for an Aug. 12 deadline to stage the vacant title fight.