Johnriel Casimero

On December 19, 2009, in Managua, Nicaragua, Casimero won the then vacant interim WBO light flyweight title, by defeating former interim WBA Light Flyweight champion César Canchila of Colombia. Canchila had a record of 28–2 coming into the bout, with his last loss coming from current WBA Light Flyweight World Champion Giovanni Segura, whom he previously defeated for the interim title. Casimero gave a spectacular performance, the fight being his first outside his home country. He was able to knockdown Canchila multiple times until the referee finally stopped the bout in the 11th round of the scheduled 12 round interim title fight.[4]

This win can give Casimero a title shot against Iván Calderón of Puerto Rico, who previously defeated Filipino boxer Rodel Mayol.[5] Casimero fought Ramón García Hirales on July 3, 2010, for his first defense of the interim WBO light flyweight title but lost by split decision.

On February 11, 2012, Casimero, and members of his team were kicked and assaulted when fans in Mar Del Plata hurled chairs and stormed the ring following his 10th-round knockout of local Argentine fighter Luis Alberto Lazarte for the IBF junior flyweight championship.[6]

After the riot, police escorted Casimero and his team to their hotel and provided protection for them. Alberto Lazarte later visited to apologize.[6]

The Philippines has filed a diplomatic protest to the Argentine government after Argentine fans attacked John Riel Casimero, a Filipino fighter, in the ring after winning the title bout.[6][7]

Philippine Foreign Affairs spokesman Raul Hernandez stated that the Philippine Embassy in Buenos Aires filed a protest with Argentina's Ministry of Foreign Affairs and is awaiting an explanation.[6] Boxer Alberto Lazarte was banned by IBF for threat, sparking a ring riot.[7]

On July 19, 2012, Casimero was declared as the regular IBF Junior Flyweight World Champion because of the inability of Ulises Solis to defend his title on or before October 30.[8]

On his first defense of the IBF junior flyweight title, Casimero faced Pedro Guevarra of Mexico on August 4, 2012. He scored a knockdown in the opening round and fought to a split decision victory.[9]

He successfully made a second defense of his title against WBC Latino light flyweight champion Luis Alberto Rios on March 16, 2013.[10] His third defense was against Felipe Salguero on October 26, 2013 and he won by eleventh-round knockout.[11]

Casimero got his first shot at a world title when he challenged Moruti Mthalane of South Africa for the IBF flyweight title on March 26, 2011.[12] He was, however, stopped by the South African in five rounds, therefore marking his second career loss.[13]

Following his win against Mauricio Fuentes and Armando Santos, Casimero moved back up to the flyweight division. On June 27, 2015, Casimero lost his return to flyweight bout via unanimous decision against IBF flyweight champion Amnat Ruenroeng in a controversial match.[14] On May 25, 2016, Casimero challenged Ruenroeng again for the IBF flyweight title and knocked him out with a vicious body shot in the 4th round.