With WBO champion Zolani Tete, WBA ruler Ryan Burnett and IBF title holder Manny Rodriguez already on board, the winner of Naoya Inoue versus Jamie McDonnell, scheduled for later this month, is also due to be added into the mix.
As Inoue is a solid favorite to defeat McDonnell in Japan on May 25, it’s the ‘Monster’ who looks the more likely to become the fourth participant for the eight-man competition.
The gala draw takes place in July, with the quarter-finals set to begin in September for what could potentially be the most entertaining tournament of the format thus far.
Inoue would certainly begin as the top man should he dispatch McDonnell as expected, with Tete, Burnett and Rodriguez all risking their title belts in pursuit of the coveted Ali Trophy.
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Exploding onto the scene in 2014 by claiming the WBC light-flyweight title in just his sixth contest, Inoue has been highly impressive in his rise to the top of the sport and is currently considered one of the best pound for pound fighters on the planet.
A super-flyweight reign lasting three years struck fear into the hearts of his rivals, although there are some UK believers that facing McDonnell at 118 pounds could be a step too far for the Japanese puncher.
As McDonnell is publicly known to be tight at the bantamweight limit, any future participation by the Yorkshireman in the WBSS would be in doubt should he end Inoue’s undefeated run in a shock outcome, whilst the four other contenders yet to be announced by the WBSS face a tall order under the current conditions.
More will be revealed in the coming weeks.