Sam Stosur's bid for a maiden grand slam title will have to wait until next year after the Australian was bundled out of the quarter-finals of the US Open by defending champion Kim Clijsters.
Fifth-seeded Stosur bravely fought back from a set down to level the match, but the second seed was too strong in the decider, winning 6-4 5-7 6-3.
It might have been the Australian's best chance to knock off Clijsters with the Belgian committing a whopping 43 unforced errors and eight double faults.
Stosur capitalised on Clijsters' wayward groundstrokes early to break in the third game, but despite serving reasonably well she lost her serve in the eighth game.
Clijsters held her own serve before breaking Stosur again to take the opening set and seemingly control of the match.
The pair traded early breaks in the second set before Stosur seized control when she broke in the ninth game to take a 5-4 lead.
She failed in her attempt to serve out the set but earned another chance two games later and this time she was successful to send the match into a deciding third set.
Neither player was able to hold their serve in the opening stages of the decider with the first six games going to the returner.
Clijsters finally got her act together and held and then broke Stosur again before finishing off the match in style with an ace to book a semi-final showdown with No.3 seed Venus Williams.
Williams clinched her last four spot with a hard-fought 7-6 (7-5) 6-4 win over Italian Francesca Schiavone.
Despite serving nine double faults and making 33 unforced errors, Williams was too strong for the reigning French Open champion and she succeeded in booking her first semi-final spot at Flushing Meadows since 2007.
Although 30-year-old Williams held a 7-0 head-to-head record against sixth-seed Schiavone, the Italian's stocks have risen since she won the title at Roland Garros earlier this year.
The first set was a tight affair in blustery conditions with neither player able to capitalise on two breaks of serve each, and it came down to a tie-breaker.
After skipping away to a 4-1 lead, Williams let 30-year-old Schiavone back into the tie-breaker but two unforced errors at 5-5 handed the opening set to the American, who is yet to drop a set in the tournament.
The second set was again an arm wrestle as both players struggled to establish a rhythm on serve.
After trading breaks in the early stages, Williams once again got on top of the Schiavone serve to close out the set 6-4.
"She played a great match," Williams said. "It's not easy to play in these conditions, it's hard to know what decisions to make, but she played excellent."
The 2000 and 2001 US Open champion is aiming to reach her first US Open final since 2002, and win her first Grand Slam trophy since the 2008 Wimbledon title.