The quarter-final matches brought up the burden of records from two long-standing match-ups featuring Novak Djokovic with Marin Cilic; as well as Roger Federer with Kei Nishikori. However, the other two match-ups herald the beginning of an unknown future.
Novak Djokovic and Marin Cilic were meeting for the 17th time in their career, with Novak having a 15-2 tally Djokovic won their first meeting in 2008 Dubai Classic and followed with 15 wins stretching till 2016, when Cilic broke the jinx by winning 6/4; 7/6 (2) at the Paris Masters. His second victory came two years later at the Queens Grasscourts where he defeated Djokovic 5/7; 7/6 (4); 6/3 for the title.
Roger Federer played Kei Nishikori in the finals of Basel Masters in 2011 and won convincingly 6/1; 6/3 for one of his nine titles on home turf. Although Nishikori won the next time in 2013 Madrid Masters as well as the quarter-finals of Miami in 2014, Federer has won all their subsequent matches from the semi-finals in 2014 Halle event till the quarter –finals of the 2018 Shanghai China Masters. The Japanese would be seeking to win their ninth face-off from a record of 6-2 held by the Swiss start.
The world’s number 5 player, Alexander Zverev of Germany had won the previous two meetings with Russia’s Karen Khachanov. Their rivalry started at the St Petersburg tournament in 2016 and Zverev won a tightly contested first set tie break to take the match.
Their second face-off was a marathon at the 2018 Roland Garros in which Zverev won 4/6; 7/6 (4); 2/6; 6/3; 6/3.Dominic Thiem of Austria holds a 2-1 career history over America’s Jack Sock ranked 23. The world number 8 won their first face-off at the 2015 Miami Masters but it was a tougher match in his victory at 2016 Indian Wells 2016 with score of 7/5; 6/7(5), 6/1. However, Jack sock won at a later meeting in Paris Masters the same year.