Kuczewska, among the favourites for the gold in the category, outclassed Germany's Juliana Kebschull to book her place in the last eight at her home event.

The Polish boxer was awarded a unanimous points victory by the judges as she maintained her pursuit of a first youth world title.

Farzana Fozilova of Uzbekistan is also through after defeating Nomin-Erdene Davaazorig of Mongolia 5-0, continuing her country's prolific showing at the Championships so far.

In the men's bantamweight class, Russia's Alexey Shendrik progressed after beating Romania's Adrian Preda.

Shendrik was chosen as the winner by three of the five judges, with the other two calling it as a draw.

Yerbolat Sabyr of Kazakhstan was a more decisive winner in his bantamweight bout against Matvejs Prokudins, stopping the Latvian early in the second round.

Robert Badalian added to the Russian success on day five of the event in the Polish city after he despatched Kazakhstan's Anvarzhan Khodziev 5-0 in their light flyweight quarter-final.

Azerbaijan's Nijat Huseynov joined Badalian in the quarter-finals thanks to a 5-0 win over Estonia's Allan Morozov.

In the evening session, the women's light welterweight category saw Latvia's Beatrice Rozentale, a boxer with European Championships experience, record a comfortable triumph against India's Nisha Gurjar.

In the men's light welterweight category Zhantoro Tashiev became the second boxer from Kyrgyzstan to reach the quarter-finals after overcoming Harutyun Hakobkokhyan by a unanimous points decision.

In the men's heavyweight category Erik Suchy of the Czech Republic overturned a first round deficit with a more aggressive style in the latter stages of the contest helping him defeat Andrei Mustet of Romania, and in the process become the first boxer from the country to reach the last eight at the event since 2008.