Ranking Divisionales: Peso Moscas

Check out my rankings within each division by clicking on the links below. If there is a lineal champion in a weight class, he is ranked No. 1.

Who is the best fighter regardless of weight class? See ESPN's pound-for-pound rankings.

For a list of the current champions in all weight classes, click here.

Note: Results through April 10. In an effort to provide the most up-to-date rankings, ESPN.com's division-by-division boxing rankings will be updated every Tuesday.

More divisional rankings

Pesado - Crucero - Semicompleto - Súper mediano

FLYWEIGHT DIVISION (UP TO 112 POUNDS)

1. Kazuto Ioka (21-1)

Japan's Ioka, who has won world titles at strawweight, junior flyweight and flyweight, has made four successful flyweight defenses, including a seventh-round knockout of interim titleholder and mandatory challenger Stamp Kiatniwat, of Thailand, on Dec. 31. Kiatniwat dropped Ioka with a right hand in the second round and swelled his right eye, but Ioka was in control for the remainder of the fight before putting him away. Defense No. 5 will come in Osaka, Japan against Thailand's Noknoi Sitthiprasert (62-4), who hasn't lost since 2005 but has faced woeful opposition.

Next: April 23 vs. Sitthiprasert

2. Johnriel Casimero (23-3)

The Philippines' Casimero, a former junior flyweight titleholder, lost a decision in Thailand in June 2015 challenging Amnat Ruenroeng for his world title. On May 25 they met in a rematch in Beijing, and Casimero exacted revenge by knocking out Ruenroeng in the fourth round to regain the belt. Casimero made his first defense on Sept. 10, heading to England and knocking out inexperienced Charlie Edwards in the 10th round on the Gennady Golovkin-Kell Brook card, but has vacated the belt and plans to move up.

Next: TBA

3. Donnie Nietes (39-1-4)
After four strawweight title defenses, the Philippines' Nietes vacated his belt and moved up to junior flyweight, where he won another title and made nine defenses. Nietes vacated his world title and moved up to flyweight on Sept. 24, cruising to a shutout decision against former junior flyweight titleholder Edgar Sosa. Next up Nietes will look to win a world title in a third division when he faces Thailand's Komgrich Nantapech (22-3) for vacant flyweight title.
Next: April 29 vs. Nantapech

4. Amnat Ruenroeng (17-1)
Thailand's Ruenroeng, who won a vacant title in 2014, racked up some quality victories among his five title defenses, including against current titlist Kazuto Ioka, McWilliams Arroyo, Zou Shiming and former titleholder Johnriel Casimero. But then he faced Casimero in a rematch on May 25 and got knocked out in the fourth round. He was one of the few pros to fight in the Rio Olympics.
Next: TBA

5. Juan Carlos Reveco (37-3)
Argentina's Reveco, a former junior flyweight and flyweight world titleholder, lost his flyweight belt in Japan by majority decision to Kazuto Ioka in April 2015, won his next fight and then lost the rematch to Ioka, getting stopped in the 11th round in December 2015. He returned from nearly a year off on Dec. 2 to score a knockdown en route to a shutout 10-round decision against Argentina-based Dominican Republic native Diego Liriano.
Next: TBA

Other contenders: Zou Shiming, Moruti Mthalane, McWilliams Arroyo, Juan Hernandez Navarrete, Vincent Legrand.