Fourth seed Alexander Zverev suffered a shock exit from the Western & Southern Open in Cincinnati as he was beaten by wildcard Frances Tiafoe in the second round.
Zverev had won his two previous meetings with Tiafoe, both earlier this season, but could not do it a third time as his American opponent fought his way into the third round with a 4-6 6-3 6-4 victory.
It was a bad day all round for the Zverev brothers as Mischa lost 6-3 7-6 (7/2) to 11th seed Pablo Carreno Busta.
Seventh seed Grigor Dimitrov looked strong in beating Feliciano Lopez 7-6 (7/5) 6-4, but will now need to be at his very best in the third round.
Dimitrov's victory set up a clash with Juan Martin Del Potro, a 6-4 6-4 winner over qualifier Mitchell Krueger. Del Potro has a perfect 5-0 record against Dimitrov to date.
Sixteenth seed Giles Muller, who defeated Rafael Nadal at Wimbeldon, suffered an early exit following a 5-7 6-4 6-4 defeat to Albert Ramos-Vinolas.
Nick Kyrgios was a 6-3 7-6 (8/6) winner over qualifier Alexandr Dolgoplov, while there were also victories for David Ferrer, Nikoloz Basilashvili, Jared Donaldson, Yuichi Sugita and Karen Khachanov in the early action.
Source: PA
