Sam Querrey stepped up his rivalry with countryman John Isner on Wednesday, the 29th-ranked American blasting 19 aces in reaching the quarter-finals of the ATP Winston-Salem Open.
Sixth seed Querrey beat 11th seed Jarkko Nieminen 4-6, 7-6 (7/4), 7-6 (12/10) a day after the 40th-ranked Finn had advanced when American Mardy Fish could not continue due to heat stroke.
Home-state hero Isner and Querrey have long been friendly rivals, with both standing over two meters tall and relying on huge serving games.
Isner was the top seed and two-time defending champion at Winston-Salem but he and third seed Tomas Berdych withdrew, citing injury concerns a week ahead of the start of the US Open.
Querrey, 25, reached the semi-finals here a year ago, losing to eventual finalist Berdych. He won his 21st match of the season, with his best showing an Auckland semi-final nearly nine months ago, and says he has his chances with the pair of major seeds missing.
"Two big kind of power guys are out. You want to take it one match at a time, but it's hard not to know that in the back of my mind that, 'Hey, I have got a good opportunity here,'" Querrey said.
Querrey, who had won just two matches over five ATP events from the end of the French Open until this week, hopes to kick-start his hardcourt season in time for the US Open.
"I have lost a lot lately, so I am literally just going one match at a time. If I can win another one that's great and another one, that's great. I don't want to look too far ahead.
"But if I do the right things and play well, I think I can make the final."
Querrey will bid for the semi-finals against Ricardus Berankis of Lithuania, who defeated Roberto Bautista Agut 6-3, 6-3.
That match will be a re-run of the 2012 Los Angeles final, claimed by Querrey over the number 126, who has won three consecutive matches for the first time this season.