But when Serena slammed a crosscourt forehand victor into an open court to break back in the next game, the roar that rocked Philippe Chatrier Court told the world she was not done yet.
And then, suddenly, after unleashing one particularly powerful backhand return victor that she punctuated with a shout, Williams was back.
The world number one kicked off his campaign with a straight-sets victory over Simone Bolelli on Tuesday but says he takes nothing for granted in the French capital.
"I lost the first set and I thought I've just got to try harder and Serena came out", said a beaming Williams after giving her skin-tight, black catsuit another outing.
Williams said that when Alexis was born, she noticed that the baby girl had her arms.
Serena Williams is officially back!
"Still, I believe you've got to distance yourself a little from the name of your opponent". I trained hard. I'm just happy to have a won match here.
Spaniard Rafael Nadal, got the better of Guido Pella of Argentina, 6-2, 6-1, 6-1 to progress to the third round, thereby dominating on his favourite clay court surface. "The draw is tricky but that can play a positive role for Serena because she can't necessarily just work her way into the tournament the way she could if she had an easy draw".
"With the light fading, Williams had done what she has done so often on the show courts of the world: rallying - with a vengeance - to win".