Sloane Stephens (right) took the first set 6-1 against 19-time Grand Slam winner Serena Williams
Serena Williams survived an early scare against the woman who last week beat her sister before reaching her 40th Grand Slam quarter-final with a 1-6, 7-5, 6-3 win over Sloane Stephens.
If the ease with which Stephens dumped Venus Williams out of the competition in only the second round raised eyebrows, there were audible gasps when she sat down at the end of the first set after just 23 minutes against her younger sister on the back of a 6-1 lead.
Williams looked borderline ill, shivering between points, rubbing her hands together and remonstrated with a ball boy when he raised an umbrella to protect her from the noon Paris sun. She needed the warmth, she protested.
Instead, it was Stephens turning on the heat, as Williams made 20 unforced errors in that nervy first set.
Serena Williams hits a volley on the way to victory over Sloane Stephens
Slowly, though Williams pulled herself together and, pushing Stephens more and more around the court she broke her midway through the second set to indicate for the first time that this match could go to the wire after all.
It took another trade of breaks, but finally the world no. 1 served out to win the second set 7-5 and it was a different woman who emerged for the third set.
Now it was Stephens looking the more leaden-footed and it took just one break to take Williams to within a game of winning the match and another one to clinch it.