Defending champion Kim Clijsters came through a desperately scrappy US Open quarter-final to set up a tantalising last-four clash with Venus Williams.
Williams, the third seed, battled past Francesca Schiavone 7-6 (7-5) 6-4 in a late-running daytime match on Arthur Ashe Stadium.
And Clijsters then opened the night session with a 6-4 5-7 6-3 victory over Australian fifth seed Sam Stosur.
Both Williams and Clijsters are chasing their third titles at Flushing Meadows.
Clijsters went into her match on an 18-match unbeaten run in New York that included title wins either side of her retirement in 2005 and 2009.
The 27-year-old Belgian also had a 3-0 record over the much-improved Stosur, who had lost to Schiavone in the French Open final earlier this year.
It was the Australian who made the better start but after winning the first set, unforced errors and fragile serving began to plague both players.
Stosur needed two chances before serving out the second set and Clijsters was in trouble in the decider as she was broken three times in a row, but Stosur could not capitalise and the reigning champion edged through in one hour and 14 minutes.
Clijsters and Williams share a 6-6 career record but the Belgian has won the last four, including a fourth-round win at Flushing Meadows 12 months ago.
Scrappy just about sums it up. Boy, when I said Kim would have a tough one if she didn't serve well I didn't think it would be as difficult, or as up and down for that matter.
Six breaks of serve for each?. Ouch.
Kim herself was joking good naturally in the post-match interview in regards to her serve saying that at least she got an ace to finish off the match.
A pretty match it wasn't, but thankfully she got through it.
Now both women have an extra day of rest (not that either of them really need it). I'm not gonna say anything in regards to Kim's next match.
Just that she wipe the slate clean and start fresh. Venus herself despite playing well can still get streaky.
Remembering last year's result 6-0 0-6 6-4 in the third, Friday will be interesting for sure.
Now I'm off to frazzle about tomorrow night's blockbuster Federer vs. Soderling.