Washington winner and fifth seed Taylor Fritz did not let a 12-minute pause for a health emergency in the stands deter him from a comprehensive 6-3 6-4 triumph over Spain's Daniel Merida at the Cincinnati Open on Tuesday.
Fritz dealt eight aces in the 83-minute victory, with Merida committing 25 unforced errors, to book a fourth-round match against Australian Chris O'Connell.
"I'll try to do what I always do, try to be aggressive on my serve," Fritz said. "That's always the best strategy."
Fritz stands 3-0 over O'Connell without dropping a set.
Italian 10th seed Lorenzo Musetti defeated American Michael Zheng 6-1, 6-3 in 71 minutes.
Andrey Rublev, losing finalist five years ago to Alexander Zverev, met a quick end at the hands of Portugal's Nuno Borges, who advanced 6-3, 6-4 in 72 minutes.
The 47th-ranked Borges ended a five-match loss streak in the rivalry.
"I played amazing," Borges said. "It means a lot to be in the fourth round. It's a big moment for me."