The Olympic taekwondo competition descended into farce when Azerbaijan coaching staff launched an angry protest at Olympic officials.
The Azerbaijan team were left fuming after a technical ruling cost Rashad Ahmadov his under 80kg semi-final bout against Iran's Yossef Karami.
They stormed the fighting area and screamed at officials while Ahmadov staged a sit-in protest.
When the competition resumed, Steven Lopez claimed the gold medal.
The double world champion overcame a hostile crowd to defeat Turkey's Bahri Tanrikulu 3-0 for his second gold in as many Olympics.
Tanrikulu, who suffered an arm injury in the opening round, was a match for Stevens early on but lost out as the problem took its toll.
Iran's Yossef Karami beat Ahmadov 9-8 to claim the bronze.
In the women's under 67kg class, China's Luo Wei took gold after beating Elisavert Mystakidou of Greece 8-6 in the final.
South Korea's Hwang Kyung-sun won the bronze medal after beating Heidy Juarez of Guatemala 5-2.