Jannik Sinner not only had to beat Holger Rune but also his illness to qualify for the quarterfinals of the Australian Open at Melbourne Park on Sunday. In the end, he stayed mentally strong to churn out a 6-3, 3-6, 6-3, 6-2 victory and keep his dream of defending his Australian Open title intact.

After the first two sets, Sinner was struggling to get going in the third set. He faced a couple of break points but somehow managed to take a 3-2 lead before calling for a medical timeout.

After the break, Sinner looked better whereas Rune, who also called for a medical timeout on the court for a knee concern, played some reckless tennis to give away the advantage.

Sinner took control in the fourth set and made his way into the last eight of the tournament. The Italian revealed that there are no injury concerns but he was not feeling good health-wise.

“I think we saw that today I was struggling physically,” Sinner said in his post-match media conference. “Came here as late as possible. I knew that it was going to be very, very difficult today. You know, playing against a tough opponent, but also playing against myself a little bit.”

“I think we saw that today I was struggling physically,” Sinner said in his post-match media conference. “Came here as late as possible. I knew that it was going to be very, very difficult today. You know, playing against a tough opponent, but also playing against myself a little bit.”

“When I’m not feeling well on court, sometimes I tend to walk a little bit on the left. But, no, injury-wise I have nothing. Just health-wise a little bit struggling, but I’m good with injuries.”

Sinner revealed that the medical timeout with the doctor helped him to recover.

“Of course, the time of the court with me and the doctor, we talked a little bit. It helped me today, and it also shows that this tournament has great organisation,” Sinner said.

Sinner will either face Alex de Minaur and 20-year-old American Alex Michelsen in the quarters on Tuesday.