Jerwin Ancajas leaves for Japan today armed with over 300 rounds of sparring as he braces for a war with defending champion Takuma Inoue in their World Boxing Association bantamweight title encounter on 24 February at the Ryogoku Kokugikan Sumo Arena in Tokyo.

"I can't tell exactly how many rounds but it's probably over 300 rounds," Ancajas said on the eve of his flight to Tokyo.

Ancajas is not exaggerating.

Before setting up camp at the Survival Gym in Magallanes, Cavite, Ancajas had trained extensively in Las Vegas when he was preparing for a 15 November clash with Inoue.

But the Japanese suffered a rib injury and the promoters were forced to postpone the match.

Instead of taking a break in training, Ancajas traveled to the Philippines and immediately resumed his buildup under the watchful eyes of head trainer Joven Jimenez.

Ancajas, who enters the ring with a 34-3-2 win-loss-draw card with 23 knockouts, will be attempting to win a second world crown in a second weight class after reigning as International Boxing Federation super-flyweight king from 2016 until 2022.

During his long reign, Ancajas made nine defenses of the 115-lb belt before surrendering it to Fernando Martinez of Argentina.

The southpaw Ancajas tried to win it back but Martinez beat him anew.

Citing that he could no longer fight to his full potential in the 115-lb division, Ancajas decided to move up in weight.

Inoue, whose younger brother Naoya is the undisputed world super-bantamweight titlist, has an 18-1 card with four knockouts.

If victorious, Ancajas will become the country's only reigning world boxing champion.