Dominic Thiem was pushed again before advancing to the Rio Open quarter-finals.
Australian Open runner-up Dominic Thiem returned to action with a win in Rio de Janeiro.
Kwon Soon-woo weathered 33 aces from Milos Raonic as the South Korean prevailed after two hours, 25 minutes midweek.
We look at the opponents Novak Djokovic has beaten at least 10 times without defeat in his career.
Novak Djokovic and Roger Federer will meet in the last four in Melbourne after the defending champion beat Milos Raonic.
We take a closer look at Novak Djokovic's form as his Australian Open campaign continues on Tuesday.
Tennys Sandgren is back in the Australian Open last eight, where he will meet Roger Federer, while Milos Raonic is also through.
Swiss maestro Roger Federer battled through five sets to join Novak Djokovic in the fourth round, but Stefanos Tsitsipas bowed out.
As several seeds fell in the men's draw, Roger Federer and Novak Djokovic reached the Australian Open third round.
Denis Shapovalov and Borna Coric are out of the Australian Open, while Novak Djokovic needed four sets to get past Jan-Lennard Struff.