Dominic Thiem had little trouble progressing into the quarterfinals of the Generali Open but second seed Dusan Lajovic bowed out on Wednesday.
With the top two seeds handed byes into the second round, French Open finalist Thiem made light work of wildcard Sebastian Ofner 6-3 6-2.
World number 26 Lajovic had no such luck against Jeremy Chardy, however, with the Frenchman coming out on top 3-6 6-4 6-3.
Chardy won 82 per cent of points behind his first serve and came from a break down in the third set to triumph.
Third seed Fernando Verdasco, who will face Lorenzo Sonego in the last eight, beat Jozef Kovalik 6-4 7-6 (9-7), while Pablo Cuevas surrendered the first set but rallied to overcome wildcard Dennis Novak.
Youngster Casper Ruud followed up an impressive performance against Pablo Carreno Busta on Tuesday with a straight-sets triumph over Matthias Bachinger.
Going up against Thiem in the quarters will be Pablo Andujar, who bettered Kitzbuhel resident and two-time champion Philipp Kohlschreiber 6-4 6-4.
Albert Ramos-Vinolas eased past compatriot Jaume Munar in Wednesday's other match.
Tsitsipas, Kyrgios, Isner, Auger-Aliassime and Raonic through to Citi Open third round
Stefanos Tsitsipas and Nick Kyrgios moved into the Citi Open third round thanks to straight-sets wins on Wednesday.
Tsitsipas, the top seed, brushed past wildcard Tommy Paul 6-3 7-5 in their second-round clash in Washington.
The Greek star converted three of his eight break points to set up a last-16 meeting with Australian Jordan Thompson.
Thompson produced one of the upsets of the day, beating 14th seed Jan-Lennard Struff 6-7 (8-10) 6-4 7-5.
Kyrgios' run also continued, the Australian serving 24 aces in a 6-4 7-6 (7-5) victory over French 11th seed Gilles Simon.
Next up for Kyrgios is Yoshihito Nishioka, who edged seventh seed David Goffin 6-7 (5-7) 6-2 7-6 (7-5) after two hours, 40 minutes.
Of the 10 seeds in action, Simon, Goffin and Struff were three of five to make exits.
Pierre-Hugues Herbert was edged by Miomir Kecmanovic 3-6 6-4 7-6 (7-5) and Atlanta champion and last year's runner-up Alex de Minaur went down to lucky loser Peter Gojowczyk 6-3 7-6 (8-6).
Three-time runner-up John Isner cruised past Hubert Hurkacz 6-4 6-4, 2014 champion Milos Raonic beat Tim Smyczek 6-1 6-4 and Felix Auger-Aliassime edged Reilly Opelka 6-4 3-6 6-4.
Benoit Paire survived against Marc Polmans with a 6-3 6-7 (5-7) 7-6 (7-5) win and lucky loser Norbert Gombos overcame Adrian Mannarino 6-4 7-6 (11-9).
Meanwhile, in doubles action, brothers Andy and Jamie Murray got through their opener by beating Nicolas Mahut and Edouard Roger-Vasselin.