Roberto Ramirez Jr. of Puerto Rico will be the third man on the ring when Filipino southpaw Dave “Doberman” Apolinario and Mexican Angel Ayala dispute the vacant International Boxing Federation (IBF) crown on Friday night (Saturday in Manila) at the Restaurante Arroyo in Mexico City.

Appointed by the New Jersey-based IBF to score the scheduled 12-rounder are Jesse Reyes of Texas, Jerry Martinez of New Mexico and Daniel Sandoval of California.

The fight supervisor — Carlos Ortiz Jr. — is from New York.

The IBF flyweight throne was declared vacant after American Jesse Rodriguez relinquished it.

And the Apolinario-Ayala encounter was brought to Mexico City after Ayala’s promoter Zanfer won the bidding against Ohashi Promotions of Japan.

Apolinario was signed by Ohashi Promotions to a contract last year.

The fighter was supposed to travel to Mexico three weeks ago to acclimatize to the weather and get used to the 7,350-ft elevation as well as adjust to the massive time difference.

But the Mexican embassy in Manila only released Apolinario’s visa last Friday, prompting his team to leave at the last minute.

Mike Pelayo, who manages Apolinario, swears the 25-year-old is no longer jet-lagged.

Promoter JC Mananquil feels his boxer is recovering well from the long flight.

The two fighters are slated to face off in a press conference on Wednesday (early Thursday in Manila).

The official weigh-in takes place the following day.

Given the key factors Apolinario are dealing with, Ayala is the clear choice as favorite to win the title.

Apolinario, however, is eager to prove them all wrong as he attempts to become the Philippines’ third reigning world champion after stablemate Melvin Jerusalem and Pedro Taduran.