By Shawn Smith

Bantamweight Shakur Stevenson entered the Rio Olympics as one of USA Boxing’s best medal hopefuls and he didn’t disappoint in his Olympic debut.

Stevenson took a unanimous decision victory over Brazil’s Robenilson De Jesus in his first fight of the Olympics after receiving a bye in the first round. The 19-year-old American is now onto the quarterfinals. A victory there will guarantee him a medal.

“It was my first day so I'll get better as the tournament goes,” Stevenson told NBC Sports’ Chris Mannix. “The crowd was booing so that made me a little nervous, but I shook it off and did what I had to do.”

Next up for Stevenson will be Tsendbaatar Erdenebat of Mongolia during the morning session of August 16. A victory there could set up an intriguing matchup against Ireland’s Michael Conlan, if he’s able to get past Russia’s Vladimir Nikitin in his quarterfinal bout.

USA Boxing’s Gary Russell also advanced to the quarterfinals with his split decision victory over Wuttichai Masuk, who entered the tournament ranked fourth. A win over Uzbekistan’s Fazliddin Gaibnazarov on August 16 will guarantee him a medal.

"(Musak) was a very technically fighter, sound,” Russell told NBC Sports’ Chris Mannix. “All the fighters, they come in here with goals of winning that gold medal. So for that, I honor him for giving me this opportunity to come in here and (showcase) all my skills.”

The first boxing gold medal of the Olympics was crowned as Hasanboy Dusmatov of Uzbekistan outclassed Yurberjen Martinez of Columbia in an entertaining affair. Dusmatov used his skill to outpoint Martinez, who used his pressure well but could not close the distance against his tricky opponent.

The largest cheer of the morning went to upset specialist Robson Conceicao who continued his incredible run with a shock defeat of Cuban Lazaro Alvarez, advancing to the gold medal match and forcing Alvarez to settle for bronze. Conceicao will find out his opponent during today’s evening session when Otgondalai Dorjnyambuu of Mongolia takes on Sofiane Oumiha of France. The lightweight gold medal match takes place on August 16.

The Day 9 evening session will also feature Great Britain’s Joshua Buatsi, coming off of a crushing knockout of Elshod Rasulov of Uzbekistan. He’ll look to follow up that performance with another victory over Adelhafid Benchabla.

Quick results

Women’s middleweight (75kg.): Iaroslava Iakushina (RUS) def. Nien-Chin Chen (TPE)

Women’s middleweight (75kg.): Dariga Shakimova (KAZ) def. Ariane Fortin (CAN)

Men’s bantamweight (56kg.): Michael Conlan (IRE) def. Aram Avagyan (ARM)

Men’s bantamweight (56kg.): Vladimir Nikitin (RUS) def. Chatchai Butdee (THA)

Men’s bantamweight (56kg.): Tsendbaatar Erdenebat (MGL) def. Dzmitry Asanau (BLR)

Men’s bantamweight (56kg.): Shakur Stevenson (USA) def. Robenilson De Jesus (BRA)

Men’s lightweight (60kg.): Robson Conceicao (BRA) def. Lazaro Alvarez (CUB)

Men’s light welterweight (64kg.): Vitaly Dunaytsev (RUS) def. Chinzorig Baatarsukh (MGL)

Men’s light welterweight (64kg.): Quanxun Hu (CHN) def. Hovhannes Bachkov (ARM)

Men’s light welterweight (64kg.): Fazliddin Gaignazarov (UZB) def. Manoj Kumar (IND)

Men’s light welterweight (64kg.): Gary Russell (USA) def. Wuttichai Masuk (THA)

Men’s light heavyweight (81kg.): Julia Cesar La Cruz def. Michel Borges BRA)

Men’s light heavyweight (81kg.): Mathieu Bauderlique (FRA) def. Carlos Mina (ECU)

Men’s light flyweight (49kg.): Hasanboy Dusmatov (UZB) def. Yurberjen Martinez (COL)