Shakur Stevenson moved into the quarter-finals ©Twitter/USABoxing

America’s Shakur Stevenson advanced to the quarter-finals of the men’s under 56 kilogram bantamweight competition after coming through a tough clash at the American Olympic Qualification Event in Buenos Aires.

The 18-year-old was impressive during the USA Boxing Olympic trials in December and made a winning debut at the World Series of Boxing last month, but was made to work hard for a preliminary win by Colombia’s Luis Miguel Ruiz Mendoza.

Stevenson began the better of the two boxers by throwing several strong punches, however his rival proved to be a resilient opponent and was able to take the entertaining contest to the finish.

The judges unanimously gave the American the verdict at the end, taking Stevenson another step closer to booking a place at Rio 2016.

"He wanted to trade with me so I beat him at his game,” said Stevenson.

“My plan was to trade with him a little bit, box when I wanted and hit him with clean shots.

"I feel good, I am ready for whoever's next."

Cuba’s Robeisy Ramirez, the Olympic gold medallist in the flyweight event at London 2012, fell to defeat in the bantamweight competition to top seed Alberto Ezequiel Melian.

Despite the bout proving a close affair, the three judges unanimously awarded the contest to the Argentine boxer by a score of 29:28.

London 2012 gold medallist Robeisy Ramirez fell to defeat
London 2012 gold medallist Robeisy Ramirez fell to defeat ©Getty Images

Ecuador’s Marlo Delgado, who represented his country at London 2012, continued his pursuit of a place at a second straight Olympic Games by beating Brazil’s Pedro Alvaro Santos de Lima.

The Ecuadorian dominated throughout the duration of the 75kg middleweight clash, with judges giving him a clear points win.

A total of 25 quota places for men and five for women up for grabs at the event in the Argentine capital.

Kenya’s Benson Gicharu Njangiru fell to a shock defeat at the African Olympic Qualification Event in Yaoundé, with the top bantamweight seed losing to Zambia’s Emmanuel Ngoma.

The Glasgow 2014 Commonwealth Games bronze medallist had been expected to emerge victorious from the contest, but the judges ultimately awarded a split decision win to his opponent.

Egypt’s Hesham Abdelaal also made a surprise exit from the division, as he was beaten via a split decision verdict by Uganda’s Atamas Mugerwa.

The continent’s best male and female boxers are competing for 36 qualification places - 30 men’s and six women’s - at Rio 2016.

However, Tanzania have been forced to withdraw from the competition due to a lack of funds.