The 21-year-old Borna Coric is through to his fifth Masters 1000 quarter-final after just one set played against the 3rd seed Juan Martin del Potro who was forced to retire after falling and injuring his knee. Both players were not on their best but it was Borna who scored the only break in game 11, holding at love a few minutes later for a 7-5 before the Argentinian decided to retire after 68 minutes.
World number 12 Kei Nishikori has scored his 36th ATP win of the season after a 7-6 6-4 triumph against Sam Querrey in an hour and 32 minutes, advancing into his fourth straight quarter-final and earning the 95th Masters 1000 win.
This was their 10th meeting and the first since Acapulco 2016, with the Japanese claiming the sixth win over the American thanks to a very solid performance on serve and with one break in the second set. Sam fought great on the fast hard court and he fired 16 aces to face just three break points, suffering the only break in the last game of the match to hand the win to his rival without a chance to reach another tie break.
Nishikori was hitting with a great depth and pace, finishing the match with 29 winners and 21 unforced errors and leaving Querrey on a 28-30 ratio which was also very decent but not enough for at least a set. Thanks to his booming serve, Sam had the advantage in the shortest points (52-37) but Kei managed to erase that deficit with a solid performance in the longer points that earned the win for him and propelled him into the first Masters 1000 quarter-final on hard courts since Miami 2017.
Querrey saved a break point in the third game of the match and Kei did the same at 2-3 when he painted a forehand down the line winner to stay on the positive side of the scoreboard. The servers were just too good in the remaining games and the tie break was inevitable, pushing each other to the limits there before Kei won it 9-7.
Sam had a set point at 6-5 on own serve but Kei won both return points to stay in the set and close it in the 16th point when Sam netted an easy forehand after 52 minutes. Nothing could separate them in the first nine games of the second set and Nishikori made a crucial move when he broke at 5-4, crossing the finish line after a backhand mistake from Querrey for his best result in Shanghai since 2011! Third round results: