Italian 10th seed Roberta Vinci beat compatriot and qualifier Camila Giorgi to reach the US Open quarter-finals for a second successive year on Monday as heavy rain brought havoc to the schedule.
Vinci recovered from 1-4 down in the first set to race away with 11 of the next 13 games to clinch a 6-4, 6-2 win over the world number 136, who had stunned former number one Caroline Wozniacki in the third round.
Vinci will face either fellow Italian Flavia Pennetta or Romanian 21st seed Simona Halep for a place in the semi-finals.
Halep had lost the first set 6-2 but was at 5-4 and set point in the second when a torrential downpour sent the players scurrying off court.
In the other last-16 match being played early Monday, Slovakia's Daniela Hantuchova led American Alison Riske 6-3, 4-4 when play also was halted.
As rain stretched the suspension past the four-hour mark, world number two Victoria Azarenka, the runner-up to Serena Williams last year, saw her scheduled last 16 clash against Serbian 13th seed Ana Ivanovic pushed back to Tuesday.
More than 30 matches were wiped off the program while five-time men's champion Roger Federer had his fourth round tie with Spain's Tommy Robredo switched from the showpiece Arthur Ashe Stadium to the Louis Armstrong arena.
Vinci was one of five women over 30 to have made the last 16 this year.
"Camila played so flat but I served really well and won lots of points that way," said Vinci, who completed business just before the deluge hit New York.
She was helped by seeing Giorgi's game completely fall to pieces on the Grandstand court as the 21-year-old hit seven double faults and 35 unforced errors.
"Camila is a great player and had nothing to lose after winning three matches in qualifying and three in the main draw. She is one for the future.
"I had lots of points to defend so I am happy to get to the quarter-finals again," added Vinci, who will make the world top-10 rankings if she wins her next match.
Despite defeat, Giorgi, who missed the entire hardcourt season in the run-up to the US Open with a shoulder injury, was content with her performances in New York, which will guarantee a return to the world top 100.
"It wasn't my day. I didn't play good. It was a great week coming back from two months without playing and I played a really good level," she said.