Cruiserweight world champion Beibut Shumenov (17-2, 11 KOs) suffered an eye injury in training on Wednesday and will not be able to defend his title against Yunier Dorticos (21-0, 20 KOs) in the main event of a special Saturday night edition of Premier Boxing Champions on FS1 and FOX Deportes, April 29 from Sam's Town Live in Las Vegas.
Shumenov-Dorticos has been postponed until Shumenov has completely healed from his injury. It will be rescheduled as soon as Shumenov is healthy enough to return to training. There is no timetable yet on when he is expected to return from the injury.
WBA Interim Featherweight Champion Carlos Zambrano (26-0, KOs) defending his title against once-beaten contender Claudio Marrero (21-1, 15 KOs) has been elevated to the main event.
Televised coverage will begin at 10 p.m. ET/7 p.m. PT and will feature undefeated Jeison Rosario (12-0, 9 KOs) taking on once-beaten Nathaniel Gallimore (17-1-1, 14 KOs) in a 10-round middleweight attraction.
"It is disappointing that Shumenov suffered an eye injury in training. Unfortunately, that's the nature of boxing,'' said Leonard Ellerbe, CEO of Mayweather Promotions. "We were looking forward to seeing him defend his cruiserweight world title against Dorticos. I hope he makes a full recovery and we can reschedule the match.
"Now, we're looking forward to Carlos Zambrano making his Mayweather Promotions debut in a scintillating match against a very tough challenger in Claudio Marrero on FS1 and FOX Deportes."
An unbeaten fighter from Lima, Peru, Zambrano turned pro in 2008 and fought nine of his first 12 bouts in the U.S. He won a South American regional title in 2012 and began moving up the featherweight rankings with a knockout victory over Devis Perez in 2014. He picked up his interim title with a unanimous decision victory over Daniel Ramirez in 2015 and defended the belt successfully against Jose Sanmartin later that year.
A former title challenger who lost a narrow decision to Jesus Cuellar in 2013, Marrero has won seven-straight bouts since then. Most recently, the 28-year-old knocked down Luis Hinojosa four times before stopping him in the fourth round in August 2016. A native of Santo Domingo, Dominican Republic, Marrero was an accomplished amateur who will be fighting in Las Vegas for the second time in his pro career.
An unbeaten fighter out of Santo Domingo, Dominican Republic, Rosario will make his U.S. debut when he enters the ring on May 16. A pro since 2013, the 22-year-old scored knockouts in his first three starts and won a Domincan welterweight title with a second round stoppage of Jose Vidal Soto in 2014. Rosario's last three starts have seen him score TKO victories over Euro Gonzalez plus previously unbeaten fighters Carlos Jairo Cruz and Rafael Lorenzo.
Originally from Kingston, Jamaica and fighting out of Evanston, Illinois, Gallimore enters this fight having won his last four bouts, all by knockout. The 28-year-old has fought professionally since 2014 and was unbeaten in his first 14 outings before losing a narrow split-decision last June. He began his 2017 with a third round stoppage of Angel Hernandez in early April.