Novak Djokovic was at the centre of another Australian Open row on Monday while Jannik Sinner needed medical attention in fierce heat to battle into the quarter-finals and Iga Swiatek won easily. But American teenage qualifier Learner Tien’s fairytale run is over after he suffered a thigh problem in a four-set defeat to Italy’s Lorenzo Sonego in Melbourne.

Jannik Sinner and Iga Swiatek are eyeing a place in the Australian Open quarter-finals on Monday while golden couple Gael Monfils and Elina Svitolina hope to extend their family odyssey.

Veteran Lorenzo Sonego reached his first Grand Slam quarterfinal after beating 19-year-old qualifier Learner Tien 6-3, 6-2, 3-6, 6-2. The 29-year-old was unstoppable on serve and handled the stifling conditions better than Tien, whose breakout tournament was highlighted by an upset of fifth seed Daniil Medvedev in round two.