Even when a little out of kilter, Williams still has the ability to intimidate almost anyone in the locker room, with the possible exception of old-stagers such as Kim Clijsters and Maria Sharapova.
As the No 12 seed (a classic example of rankings overruling common-sense), she is on course for a quarter-final against Sharapova, who surged past Jamie Hampton yesterday in a 6-0, 6-1 victory.
But one thing Williams will not now be doing is competing in the mixed doubles as expected with fellow American Andy Roddick.
Roddick cut a dejected figure as he withdrew after three sets of his much-anticipated night match against long-time rival Lleyton Hewitt.
The cause was a hamstring injury suffered early in the second set, which restricted his movement to what he described as “60 or 70 per cent extension”.
“You can try to ham and egg it against a lot of guys,” Roddick added.
“But he [Hewitt] is really intelligent. He knew what was going on.
"You’re out there and you’re wondering, ‘Listen, even if this goes your way, you’re not going to play in two days’.
"So it’s a miserable, terrible thing being out there compromised like that. It really sucks.”
Earlier, Novak Djokovic had made an untroubled passage to the third round when he beat Santiago Giraldo, of Colombia, 6-3, 6-2, 6-1.