Italy's Alberta Brianti defeated Pavlyuchenkova 6-3, 4-0, as the promising Russian retired with a right shoulder injury during the second set.
Rezai rolled over Kazakhstan's Galina Voskoboeva 6-2, 6-4 and Italian favorite Roberta Vinci beat Spaniard Lourdes Dominguez Lino 4-6, 6-4, 7-6 (7-3).
Additional first-round wins saw Belarusian Olga Govortsova beat Italian Maria Elena Camerin 6-3, 6-1 and American Varvara Lepchenko beat Italian wild card Corinna Dentoni 6-3, 6-2.
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