Peng Shuai eased into the last eight of the Tashkent Open with a 6-1 7-5 victory over Dutch qualifier Arantxa Rus.

The top seed from China, Peng will face sixth seed Monica Niculescu in the quarter-finals.

The Romanian had been leading 6-3 3-4 in her second-round match with Yaroslava Shvedova when the Kazakhstan player retired due to illness.

Another Romanian, Sorana Cirstea, also claimed her place in the next round thanks to a 6-1 6-4 success over Russia's Anna Lapushchenkova.

Cirstea's next opponent will be Portugal's Michelle Larcher de Brito, who was a 6-4 6-1 winner against Tatiana Poutchek of Belarus.