Jannik Sinner advanced to the Australian Open quarter-finals, overcoming illness, while Lorenzo Sonego ended Learner Tien's dream run. Madison Keys surprised Elena Rybakina, and Elina Svitolina uplifted Ukraine by defeating Veronika Kudermetova.

Day nine of the Australian Open saw Lorenzo Sonego and Elina Svitolina advance to the quarter-finals with impressive wins. Jannik Sinner overcame a medical timeout to beat Holger Rune, while Madison Keys stunned Elena Rybakina.

Jannik Sinner battled through illness to reach the quarter-finals of the Australian Open on Monday as his Italian compatriot Lorenzo Sonego ended teenager Learner Tien's fairytale run.

Elina Svitolina of Ukraine gestures during her fourth round match against Veronika Kudermetova of Russia at the Australian Open tennis championship in Melbourne, Australia, Monday, Jan. 20 ...

MELBOURNE, Australia (AP) — Elina Svitolina rallied from 4-1 down and took 11 of the next 12 games in a 6-4, 6-1 victory over Veronika Kudermetova on Monday to reach the Australian Open ...

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 ... Svitolina beat Veronika Kudermetova -- then ...

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