Peng dispatched Arantxa Rus, 6-1, 7-5, in the highlight match of Thursday's second-round play at the hard-court tournament. She will next go against sixth-seeded Monica Niculescu, who advanced when Yaroslava Shvedova, trailing 6-3, 3-4, retired due to illness.
No. 3-seeded Sorana Cirstea ousted Anna Lapushchenkova, 6-1, 6-4, and Michelle Larcher de Brito beat Tatiana Poutchek, 6-4, 6-1, in other second-round matches Thursday.
Cirstea drew Larcher de Brito for Friday's quarterfinals while fourth-seeded Sabine Lisicki plays Urszula Radwanska and No. 5-seeded Magdalena Rybarikova faces Ioana Raluca Olaru.
The tournament continues through Sunday when the 2008 Tashkent Open titlist will collect $22,925.