The Italians won 3-2 at Fed Cup style match which was played only by a tie-break.
Schiavone, 2010 French open champion, beat the Williams sisters in their singles, while Pennetta beat Venus, but lost to Serena.
However, the eagerly anticipated contest that was double Olympic champion Williams sisters - who have 20 Grand Slam singles titles between them, 12 doubles titles together, and four mixed titles Games - who came down from the win.
