Alex de Minaur set up a last-16 showdown with top seed John Isner before wet weather cut short play at the Atlanta Open.
Only two matches were completed as rain wreaked havoc at the ATP 250 tournament in Atlanta on Monday.
Australian youngster De Minaur was fortunate to beat the rain as the talented 19-year-old won his opener.
De Minaur – who reached the third round at Wimbledon – rallied past Hubert Hurkacz 1-6 7-6 (7-0) 7-6 (7-5) to earn a clash with reigning champion and four-time winner Isner.
"It wasn't the prettiest of wins, but it's a very important win for me," De Minaur, a finalist at the Sydney International in January, said. "I managed to dig deep, stay tough and beat a quality opponent."
Eastbourne runner-up Lukas Lacko also advanced with a 6-2 6-2 victory over Prajnesh Gunneswaran.
Ivo Karlovic had won the opening set 6-2 and was tied at 5-5 against Donald Young in the second when the rain set in.
The pair will return on Tuesday, while the weather prevented Ryan Harrison and James Duckworth from taking to the court.