Germany’s Alexander Zverev was the only one of the top four seeds to escape the upset bug during quarterfinal action on Friday at the Terra Wortmann Open in Halle, Germany.

The top-seeded Zverev held off Belgium’s Raphael Collignon 7-6 (10), 7-6 (2) as both players uncorked 14 aces and lost no service games during their two-hour battle.

No. 2 seed Felix Auger-Aliassime of Canada earned three match points against Frances Tiafoe, but the American fended off each one to earn a 3-6, 6-3, 7-6 (12) victory.

No. 3 seed Ben Shelton reached match point against No. 5 Taylor Fritz, but he couldn’t convert as Fritz rallied for a 6-7 (5), 7-6 (8), 7-6 (3) triumph. Fritz unleashed 24 aces and stopped all four of Shelton’s break points as both Americans maintained their serve throughout.

While Zverev and Fritz will meet in one semifinal on Saturday, the unseeded Tiafoe faces unseeded Daniel Altmaier in the other. The German wild card earned his spot with a 6-4, 6-7 (6), 6-4 victory over No. 4 seed Daniil Medvedev of Russia.

HSBC Championships

Unseeded Brandon Nakashima needed just 93 minutes to knock out top-seeded Alex de Minaur of Australia with a 7-5, 6-3 quarterfinal victory in London. Nakashima owned a return rating of 184 as he won 30.8% (16 of 52) of the points on de Minaur’s serves.

Nakashima will meet No. 7 seed Francisco Cerundolo in Saturday’s semifinal action as the Argentina native defeated Great Britain’s Arthur Fery 7-6 (1), 3-6, 6-4.

No. 8 seed Tommy Paul upset No. 4 seed Alejandro Davidovich Fokina of Spain by a 6-3, 7-6 (4) count as Paul held his serve throughout. Paul will meet unseeded Ugo Humbert in the other semifinal as the left-handed Frenchman stopped Australia’s Rinky Hijikata 6-1, 6-2.

–Field Level Media