The action kicks off at 2 p.m. with the match between Czech rising star Tomas Machac and British No. 7 seed Jack Draper. Machac surprised the tournament's No. 3, Bulgarian Grigor Dimitrov, in the round of 16. Draper, the No. 7 seed at the Erste Bank Open, on the other hand, had no problems defeating Thiem's opponent Luciano Darderi in two sets.

In the second match of the day, title favorite Alexander Zverev will face Lorenzo Musetti. The young Italian did not have to play his round of 16 match as his opponent Gael Monfils (FRA) had to withdraw before the match due to illness. Zverev was allowed onto the court, but had no problems at all in his two-set victory against the American Marcos Giron. Musetti should now be the first real test for the German.

Matteo Berrettini and Karen Khachanov will meet in the third match (not before 6 p.m.). Both players had to go through three sets in their round of 16 matches. Berrettini against Frances Tiafoe on Wednesday, Khachanov against Brandon Nakashima on Thursday. The Italian has a 4-0 lead in the direct comparison, although the last time the two met was almost four years ago in the third round of the Australian Open.

The fourth and final quarter-final will be contested by Czech shooting star Jakub Mensik and Alex de Minaur. Mensik, who had to go through qualifying in Vienna, has so far surprised with victories against the Australian number 8 seed Alexei Popyrin and the Serb Miomir Kecmanovic. And the journey doesn't have to be over against de Minaur if Mensik can continue his strong service performance in the quarter-finals. The Czech served no fewer than 23 aces against Kecmanovic. A tough task for any opponent. On the other hand, Alex de Minaur's day in the round of 16 was over after just 74 minutes on Thursday because his opponent, Flavio Cobolli, had to retire with an injury in the second set.