Riku Masuda’s eighth-round stoppage win last month over the faded but still dangerous Nonito Donaire has been rewarded with big bumps from both the WBA and the WBO.

Going into March, the WBA had Masuda slotted No. 4 at bantamweight while Donaire was No. 1. In the WBA’s latest monthly ratings update, released April 1, the fighters have now switched positions, with Masuda at No. 1 and Donaire at No. 4.

The WBO meanwhile, previously had Masuda at No. 6 and Donaire at No. 7. Its update, also released April 1, saw Masuda leap up to No. 1 while Donaire fell out of the top 15 altogether.

The WBO bantamweight titleholder is Christian Medina, 27-4 (19 KOs), who is coming off a unanimous decision victory over Adrian Curiel in February.

The WBA belt is held by Seiya Tsutsumi, 13-0-3 (8 KOs), who coincidentally gave Masuda the sole blemish on his record.

Masuda, 10-1 (9 KOs), a 28-year-old from Tokyo, lost a decision to Tsutsumi in August 2023. Tsutsumi would go on to unseat Takuma Inoue for the WBA 118lbs title in October 2024. But Tsutsumi was named the WBA’s “champion in recess” when he was injured and therefore unable to defend against interim titleholder Antonio Vargas, who was subsequently elevated.

Vargas and Tsutsumi then changed spots last year, with Vargas becoming “champion in recess” because a family tragedy meant he couldn’t defend against a returning Tsutsumi.

Tsutsumi won a split decision over Donaire this past December. But facial fractures Tsutsumi suffered in that win hadn’t healed enough for Tsutsumi and Vargas to face off on a scheduled April 11 date.

It remains to be seen whether the WBA will switch Tsutsumi back to “champion in recess” again, re-elevate Vargas and order him to defend against Masuda, or if the sanctioning body will instead wait for Tsutsumi-Vargas to be made again.

The WBA’s top 15 bantamweight rankings have Masuda followed by Tenshin Nasukawa, Kazuto Ioka, Donaire, Andrey Bonilla, Daigo Higa, Yoshiki Takei, Michael Angeletti, Yelshat Nikhemttolla, Kenneth Llover, Muhammad Waseem, Jordan Orozco Hernandez, Emanuel Moreno, Katsuma Akitsugi and Shori Umezu.

The WBO’s top 15 bantamweight rankings have Masuda followed by Juan Francisco Estrada (who was bumped from the No. 1 position), David Cuellar, Takei, Andrew Cain, Akitsugi, Emmanuel Rodriguez, Ephraim Bui, Rubens Diego Dos Santos, Jason Moloney, Nasukawa, Orozco Hernandez, Jeyvier Cintron, Llover and Alexandro Santiago.

David Greisman, who has covered boxing since 2004, is on Twitter @FightingWords2. David’s book, “Fighting Words: The Heart and Heartbreak of Boxing,” is available on Amazon.