Williams, who has been stuck on 21 majors since lifting the Venus Rosewater dish at Wimbledon 11 months ago, had been expected to wallop little-known Kazakh Yulia Putintseva in their quarter-final.
After all, Williams had yet to drop a set at this year’s championships, she is a three-times Roland Garros champion and was playing in her 44th grand slam quarter-final.
Putintseva, in contrast, had never advanced this far in a major before, had never beaten a world number one and was ranked a lowly 60th.
However, it was the 21-year-old who came out all guns blazing after making her debut on a chilly Court Philippe Chatrier decked in a baggy tracksuit.
So out of sorts was Williams’ normally overpowering game, that she produced 11 unforced errors before Putintseva committed even one.
By the end of the first set, that tally stood at 24-2.
With one mistake, following an error, following another blooper, the American got so desperate that she even resorted to switching her racket to her left hand for one point – and fluffed that too.
“I just kept hitting balls out. I just wasn’t firing the way I wanted to,” said the 34-year-old, who is looking to draw level with Steffi Graf’s professional era record of 22 grand slam titles.
“I definitely knew I needed to do something different if I was going to stay in the tournament. Honestly, at one point I didn’t see the light at the end of the tunnel.”
At no time was that tunnel darker than when she was just five points from being beaten by a player who was four years old when the American won the first of her major trophies at the US Open in 1999.
But for a woman who has survived countless trials over the course of her previous 336 grand slam matches – with her win-loss record standing at 295-41 – she could see only one outcome.
“I always try to have a plan B and C and go from there,” said the 34-year-old, who will be back in action for a third day running on Friday when she faces Dutch outsider Kiki Bertens for a place in the final.
“In the beginning of the second set I started playing better, but then I let her come back. I was not the most positive mentally, but obviously I didn’t want to stop.”
She certainly did not stop despite amassing a rather unflattering 43 unforced errors to just 16 from Putintseva.
What mattered more by the end though was that her winners count stood 36-18.
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