Caroline Wozniacki was three games from French Open elimination when her French Open fourth-round clash with Daria Kasatkina was suspended under fading light in Paris.
The Australian Open champion was trailing Kasatkina 7-6 (7-5) 3-3 when officials ordered the pair to return on Monday to complete the match.
While second-seeded Wozniacki faced a restless night’s sleep, US Open champion Sloane Stephens and fellow American Madison Keys were already safely through to the last eight.
Unlike her third-round escape against Camila Giorgi, Stephens never gave Anett Kontaveit a sniff, winning the last 11 games to reach the quarter-finals for the first time with a 6-2 6-0 demolition of the Estonian.
Stephens had fallen at the fourth hurdle five times previously but needed just 52 minutes to break through and complete a grand slam set of quarter-final showings in Melbourne, Paris, London and New York.
“Super cool. Isn’t it exciting?” she said.
“Obviously doing well at any slam, making the fourth round four times or whatever is pretty good, but to finally get over that hump of quarter-finals feels very nice.”
Runner-up to Stephens at Flushing Meadows last year, Keys was the first woman through to the quarters after ending Mihaela Buzarnescu’s inspired run with a 6-1 6-4 victory over the Romanian.
The 13th-seeded Keys, who is yet to drop a set, plays Yulia Putintseva next after the Kazakh youngster upset Czech 26th seed Barbora Strycova 6-4 6-3 to advance to the final eight for the second time in three years.
“Today I was very tough mentally,” said the world No.98.
“It was a fourth-round match and everyone is play good now. You just have to fight for every point.”
Three-times champion Serena Williams can make it three Americans in the last eight if she beats Maria Sharapova on Monday.