Top seed Andy Roddick used his serve to beat Slovenian Grega Zemlja 6-4, 6-4 in the second round of the Washington Classic on Tuesday. Roddick blasted just four aces but won 90 per cent of his first serves.
In other matches at the U.S. Open warm-up, Spanish third seed Fernando Verdasco beat German Michael Berrer 4-6, 7-5, 7-6 while fourth seed Marin Cilic of Croatia eased past Denis Istomin of Uzbekistan 6-4, 6-2.
Zvonareva enjoys a winning return
San Diego: Wimbledon finalist Vera Zvonareva enjoyed a successful return to hardcourt action with a 6-0, 3-6, 6-4 win over Dominika Cibulkova in the first round of the San Diego Open on Tuesday.
The Russian was joined by Svetlana Kuznetsova, who upset eighth seed Yanina Wickmayer 6-3, 2-6, 6-1.
In other matches, Agnieszka Radwanska of Poland beat Chanelle Scheepers of South Africa 7-5, 6-3, while Italian Flavia Pennetta beat Kateryna Bondarenko (Ukraine) 6-2, 7-5.