Rosillo defeated Armenian Artur Aleksanyan, 2016 Olympic champion, in the battle for the crown in a legendary final.
The bronze medals in this category went to the Czech Artur Omarov and the Iranian Mohammad Hadi Saravi.
This was the first gold for Cuba in the contest and tomorrow it will seek the second, through Luis Alberto Orta, in the 67 kilograms, Greek style.
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