Top-seeded Stanislas Wawrinka of Switzerland advanced comfortably but second-seeded Mikhail Youzhny of Russia quit during his second-round match due to a stomach infection in the Chennai Open on Wednesday. Wawrinka defeated Benjamin Becker of Germany 6-3, 6-1, while Youzhny retired ill against Dudi Sela of Israel while trailing 3-1 after 24 minutes. ''It's a stomach problem,'' Youzhny said. It's quite slow and humid out there and it was raining a bit.'' Youzhny's compatriot, Alexander Kudryavtsev, also retired while leading 6-1, 0-3 against Aljaz Bedene of Slovenia. More...