The Mexican’s open defence was exploited by Martinez in the second round, but strong performances in both the first and third saw the 22-year-old set up a last-four encounter with the Dominican Republic’s Victor Daniel Santillan.  

Velasquez edged the punch exchanges in the final three minutes, regularly hitting the target with fizzing combinations, to get the better of the Central American and Caribbean Games silver medallist.

"I had to do my very best and we had to build a smart tactic against Yubergen Martinez, who is not only a strong boxer but a quick one," said Velasquez, whose success at Toronto 2015 last month secured his second Pan American Games gold medal. 

"I was trying to be a hard target for the Colombian boxer, and counter-attacked him as many times I could.

"It was a good performance, and I am looking forward my next bout in Vargas."

Success for Cuban light flyweight Joahnys Oscar Argilagos Perez was the first of five on the day for his country across the weight categories as the 18-year-old junior world champion triumphed against Argentina’s Leandro Blanc.

In the bantamweight division, Brazil's Robinelson De Jesus Vieira beat fellow London 2012 Olympian Alberto Melian of Argentina by split decision in an all-South American bout, while the Dominican Republic’s Hector Luis Garcia, a silver medallist at Toronto 2015, proved too strong for the Cayman Islands’ Tafari Ebanks.

A highly productive day for Cuba, meanwhile,  continued as Toronto 2015 gold medallist Andy Cruz Gomez controlled his bantamweight bout against Ecuador’s David Padilla.

Venezuela’s Luis Arcon overcame Costa Rica’s Eduardo Sanchez at light welterweight, a division in which Cuba’s Yasnier Toledo Lopez dominated his quarter-final over Argentina’s Ronan Nahuel Sanchez.

The biggest surprise of the day came at middleweight as Ecuador’s Marlo Delgado saw off defending champion Jorge Luis Vivas of Colombia.

Delgado goes on to face Venezuela’s Endry Saavedra in the semi-finals, where he will be joined by Cuba’s Arlen Lopez, conqueror of American Anthony Campbell.

In the heavyweight division, Argentina’s Yamil Alberto Peralta got the better of Chile’s Miguel Angel Veliz, while Erislandy Savon defeated the United States' Joshua Temple to secure Cuba’s fifth victory of the day.

The semi-finals are scheduled to take place tomorrow with all the weight classes set to feature. 

As well as securing a medal, all 40 semi-finalists have also earned quota places for this year’s International Boxing Association (AIBA) World Boxing Championships in Doha in October. 


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