The night after Roger Federer was stunned by Greece's Stefanos Tsitsipas, there was another sniff of an upset at Rod Laver Arena as 22-year-old Medvedev shook the Serb with a furious assault of power hitting.
Yet the Russian wearied in the constant attrition, and top seed Djokovic ultimately cruised to victory, having passed easily his biggest test at the tournament.
The world No. 1 will continue his bid for a hat-trick of grand-slam titles and a record seventh at Melbourne Park against eighth seed Kei Nishikori.
Earlier on Monday, Nishikori was involved in an epic battle against Pablo Carreno Busta, eventually coming through 6-7, 4-6, 7-6, 6-4, 7-6 after 5hr 5min. SHARE THIS STORY USING ANY OF THE BUTTON BELOW ⬇ PLACE YOUR TEXT ADVERT BELOW ⬇⬇⬇