Jannik Sinner, the world No 1 and defending champion, looked to be heading out of the Australian Open until he was rescued by a controversial medical time-out.

In the Australian Open Round of 16 on Sunday, No. 1-ranked Jannik Sinner takes on No. 13 Holger Vitus Nodskov Rune.Sinner enters the Round of 16 after his three-set win on Saturday over Marcos

Jannik Sinner is through to the Australian Open quarterfinals after a drama-filled fourth-round win over Holger Rune. World No. 1 Sinner won in four sets, 6-3. 3-6, 6-3, 6-2, but this did not tell the story of a contest defined by injury.

Defending champion Jannik Sinner has moved into the quarterfinals at the Australian Open after beating Holger Rune during a match slowed down by medical timeouts for each player and a delay because the net got knocked loose.

Sinner was joined in the quarter-finals by countryman Lorenzo Sonego, who is through to this stage at a grand slam for the first time after ending the run of 19-year-old American Learner Tien with a 6-3 6-2 3-6 6-1 victory.

The screw holding the net in place at the Australian Open’s main stadium has been jarred loose during defending champion Jannik Sinner’s fourth-round match against Holger Rune

Jannik Sinner was wobbling around like a drunken sailor. We witnessed controversial tit-for-tat medical time-outs with Holger Rune, stare-offs, momentum swings, terrible points, epic rallies, erratic sets and a wildly see-sawing match.

Defending champion Jannik Sinner has defeated 46th-ranked Marcos Giron of the U.S. 6-3, 6-4, 6-2 at the Australian Open.

Jannik Sinner is a shooting star in tennis, and the World No. 1 has already received a few nicknames and monikers from fans. Some like to reference Sinner's bright red hair with "Carrot Top," while others give the nod to his childhood name as the "Fox.

Jannik Sinner moved into the Australian Open quarterfinals Monday by eliminating Holger Rune in a match paused by medical timeouts and the net detaching from the court.