Robson Conceicao won host Brazil's first ever Olympic boxing gold medal on Tuesday, the lightweight drawing inspiration from a vociferous home support to secure a unanimous points victory over Sofiane Oumiha of France.

Oumiha, greeted upon his entrance by loud booing from a passionate soccer-style crowd who continued to wave Brazilian flags and crank up the volume throughout the bout, took the silver.

Cuban top seed Lazaro Alvarez, beaten by the Brazilian in the semi-finals, and Mongolia's Otgondalai Dorjnyambuu were the bronze medallists.

The 27-year-old from Salvador in northeastern Brazil was on top from the opening bell, his every punch met with roars of approval from a crowd that dwarfed the meagre turnout for Monday’s heavyweight final.

With chants of ‘Brazil, Brazil’ echoing around the arena, Conceicao claimed the first two rounds on all three judges’ scorecards.

The man in the red corner even turned crowd-pleaser in the second -- dropping his guard and showboating, with the odd feint thrown in -- before Oumiha came back stronger in the third.

By then, the fight was as good as won and the judges would have had a riot on their hands had the gold gone to anyone but their man.

Conceicao raised his fist to acknowledge the crowd’s support long before the referee formally lifted it to declare him the winner.

As he stood on the podium with the gold around his neck, the crowd stood and sang the national anthem.

Brazil won three boxing medals at the 2012 London Games, their first in the ring in 42 years, with Esquiva Falcao Florentino’s middleweight silver their best performance until Tuesday.