Simona Halep has said that it is "unbelievable" to be through to the quarter-finals at the US Open for the first time in her career.
The second seed came from a set down and struggled with a hamstring problem as she beat Germany's Sabine Lisicki in the fourth round, setting up a last-eight meeting with former world number one Victoria Azarenka.
Speaking on court after the match, the Romanian said: "It's unbelievable to reach my first quarter-final at the US Open. It was a crazy match. I'm pretty tired but I would have been very unhappy with myself had I lost."
It was just the second time in six appearances at the event in New York that Halep had reached the fourth round.