Serena Williams passed her toughest test so far at the US Open to beat Karolina Pliskova and reach the semi-finals for a ninth consecutive time.
Williams, seeded 17th, trailed 4-2 in the first set but hit back to win 6-4 6-3 against the Czech eighth seed.
The American, 36, is seeking her first Grand Slam trophy since giving birth to daughter Olympia last September.
If she wins it would be her 24th major title – equalling Australian Margaret Court’s all-time record.
“I don’t think I have another 10 years of having opportunities to be able to play and win championships,” said former world number one Williams.
“Every match really means a lot to me. I kind of go out there and I just do the best that I can.”
Williams faces Latvia’s 19th seed Anastasija Sevastova, who knocked out American defending champion Sloane Stephens earlier on Tuesday, in the last four on Thursday.
Six-time champion Williams has reached the semi-finals in her past nine appearances at Flushing Meadows, although missed the tournament in 2010 with a foot injury and last year because she was pregnant.