Defending Wimbledon champion Serena Williams cruised into the second round with a 6-3 6-3 win over fellow American Jill Craybas.
Williams was not at her best, making only 53% of first serves and producing 21 unforced errors, but she still had too much firepower for her 67th-ranked opponent.
Despite claiming three games in the opening set, Craybas hit only one winner - a backhand volley - in the entire set.
Williams, who will now play Belgian's Els Callens, said afterwards that the departure of men's top seed Lleyton Hewitt had put her on edge.
"I was a bit nervous today and I don't know why. I didn't want to lose in the first round but once those first few games were over I was okay," said the American.
"Obviously I was aware what happened yesterday and I didn't want to create history by
having both defending champions going out in the first round."
Russian 15th seed Elena Dementieva beat Germany's Angelika Roesch 6-2 6-1.
And 10th seed Anastasia Myskina advanced after her Slovak opponent Henrieta Nagyova was forced to retire.
Elsewhere, two seeded players fared less well.
American number 19 seed Meghann Shaughnessy fell to Hungarian Aniko Kapros 6-3 6-2.
Thailand's Tamarine Tanasugarn, the 32nd seed, was upset by Japan's Akiko Morigami 6-4 6-3.
Jennifer Capriati joined Kapros in the second round with a straight-sets win over Switzerland's Myriam Casanova.
On Court Two, Russian glamour girl Maria Sharapova swept aside American Ashley Harkleroad in straight sets.
French Open champion Justine Henin-Hardenne made light work of Ukrainian Julia Vakulenko, winning 7-5 6-1.