Alexander Zverev suffered a huge shock in the first round of the Swiss Indoors Basel on Tuesday as he succumbed to a straight-sets defeat to Taylor Fritz.
Zverev had been in tremendous form since a disappointing fourth-round exit at the US Open, reaching the semi-finals of the China Open and the final of the Shanghai Masters.
However, the second seed fell back down to earth in Switzerland as Fritz claimed his fourth top-10 win of the year.
The American fired down 37 winners in a 7-6 (9-7) 6-4 triumph that marked the biggest of his career by ranking.
"I played really solid, so it feels good to get that [win] instead of him getting me for the third time in a row," Fritz said. "I got out there today and the sliders [on my serve] were working well."
HUGE win for @Taylor_Fritz97
— ATP Tour (@atptour) October 22, 2019
He's defeated No. 2 seed Alex Zverev 7-6 6-4 to move into the second round at the #SwissIndoorsBasel. pic.twitter.com/29dTBYdnZ5
Stefanos Tsitsipas, who ended Zverev's China Open run, had no issues as he saw off Albert Ramos Vinolas 6-3 7-6 (8-6).
The Greek remains on course for a potential semi-final with Roger Federer, whose next obstacle in his bid for a 10th title in his hometown will be Radu Albot, who overcame Dusan Lajovic in three sets.
Roberto Bautista Agut and Fabio Fognini earned straight-sets wins over Marius Copil and Alexei Popyrin respectively, while Richard Gasquet defeated Juan Ignacio Londero and Reilly Opelka beat Cristian Garin.
NEW LEVELS of tennis were reached today
— ATP Tour (@atptour) October 22, 2019
Top seed Thiem outlasts Tsonga's test to reach the @ErsteBankOpen 2R
: @TennisTV pic.twitter.com/yqt7sSjpl6
At the Erste Bank Open in Vienna, top seed Dominic Thiem started his quest for a second title in his home country this year with a 6-4 7-6 (7-2) defeat of Jo-Wilfried Tsonga.
There were shocks in the Austrian capital as seventh seed Guido Pella went down 6-4 6-4 to Aljaz Bedene while Milos Raonic was beaten by Chung Hyeon 6-4 7-5.
Aside from his appearance at the Laver Cup, Tuesday marked Raonic's first match since retiring from the Rogers Cup with a back injury, and the former Wimbledon finalist saw a second-set comeback fall short.
Eighteen-year-old Jannik Sinner, fresh from his run to the European Open semi-finals, continued his fine form by overcoming Philipp Kohlschreiber. Gilles Simon defeated Feliciano Lopez in straight sets and Fernando Verdasco won a three-set tussle with Nikoloz Basilashvili.