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.