Vienna – The two top tennis stars at the Erste Bank Open in the Wiener Stadthalle easily reached the quarter-finals on Thursday. Jannik Sinner got rid of his second round task against his Italian compatriot Flavio Cobolli with a score of 6:2,7:6(4). Previously, the German Alexander Zverev was safe against the Italian Matteo Arnaldi at 6:4,6:4. Sinner meets Alexander Bublik on Friday, Zverev faces Tallon Griekspoor.