Simona Halep did something no one else was able to do against Serena Williams at the US Open on Wednesday but still could not stop the world number one from advancing to the semi-finals of the year’s final grand slam.

The scrappy fifth seeded Romanian managed to take the first break points from Williams during the Flushing Meadows fortnight and the only set surrendered by the top seed but at the end of the day the result was the same, the 34-year-old American walking off court with a 6-2 4-6 6-3 win.

The victory also kept Williams on course for a record seventh US Open crown which would be her 23rd grand slam title moving her past Steffi Graf for the most in the Open Era and one shy of the great Margaret Court at the top of the all-time list with 24.

“I knew I could play better and I kind of feel like I lost my rhythm in the second set,” said Williams, who will next face 10th seeded Czech Karolina Pliskova, a 6-2 6-2 winner over Croatian teenager Ana Konjuh, for a place in this weekend’s final.

“I knew if I wanted to win this I had to step it up in the third set.

“I didn’t take some opportunities that I had. I really had some chances there and I didn’t take them, and I let that get the better of me.”

What had appeared to be a straight sets stroll into the last four for Williams turned into a tense battle when Halep dug in during an entertaining second set packed with pulsating rallies and brilliant shots that saw the Romanian fend off all 12 break points she faced.

But Williams, playing in her 46th grand slam quarter-final, would not be shaken and took the only break to go up 3-1 in the decider and then serve out for the win.