Kom, who followed her most recent World Championship success in 2010 with an Olympic bronze medal at London 2012, was marking her return following a year out of the sport after winning gold at the 2014 Asian Games in Incheon.

She produced a strong performance to beat Venezuela's Karlha Magliocco in her under 51 kilograms quarter-final yesterday but found Fuchs a challenge too far in today's last four tussle.

It marked another breakthrough for the American in her battle to secure Rio 2016 qualification following her Olympic Trials victory over another London 2012 bronze medallist in Marlen Esparza in October.

Fuchs will now face Britain's Lisa Whiteside in the final.

She defeated Grazidi Jesus of Brazil today.

Whiteside also has an illustrious team-mate to overcome if she is to secure Rio qualification, reigning champion Nicola Adams, who is not present in the Brazilian city this week.

Six home fighters did make it through to finals today, including Flavia Figueiredo, who beat Australian teenager Caitlin Parker in the under 75kg division to set up a final with Morocco's Khadia Madi.

Morocco’s current world champion and World Series of Boxing (WSB) star Mohammed Rabii beat Juan Pablo Romero of Mexico in their under 69kg bout.

Uzbekistan secured three final slots, with world champion Hasanboy Dusmatov overcoming Shyam Kakara of India.

"The Rio test event is very competitive but after my WSB season and main AIBA Boxing events I feel I can win the gold medal here in Brazil," Dusmatov said. 

"It is great that our International Federation has staged this competition in Rio and to be able to acclimatise for next year's competition."

Hurshid Tojibaev and Murodjon Akhmadaliev also won in their respective under 60 and under 56kg events

On a mixed day for Britain, Samuel Maxwell, Joshua Buatsi, Frazer Clarke and Chantelle Cameron all made it through in their under 64, under 81, over 91 and women's under 60kg events, but Luke McCormack and Galal Yafai each missed out.

Another impressive winner was The Netherlands' Peter Mullenberg, who beat Michel de Souza of Brazil to set up a light heavyweight final with Buatsi.

All the finals are due take place  tomorrow.

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