Just two first-round matches were on the opening day schedule.
The fifth-seeded Hingis won the first nine games against Germany's Anna-Lena Groenefeld and posted a 6-0, 7-5 victory in just 75 minutes.
Hingis, who won this title in her last appearance in 2000, will next play the winner between France's Nathalie Dechy and Jarmila Gajdosova of Slovakia in the second round.
Srebotnik beat Pierce 6-3, 7-5 win. The Slovenian had just one break point in the first set and converted it, while Pierce failed on each of her six break-point chances during the set.
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