SHANGHAI: A bad season continued for Andy Roddick today as the American was forced to retire after injuring his knee in a second-round match at the Shanghai Masters.

Swiss Stan Wawrinka advanced 3-4 after Roddick — next in the qualifying queue for a place in the eight-man World Tour Finals in London in November — hurt his knee at 40-all.

Three other seeds in Shanghai advanced after byes at the penultimate Masters 1000 of the season. Russian No 6 Nikolay Davydenko advanced over compatriot Igor Kunitsyn 6-4, 6-2.

Chile Fernando Gonzalez, No 10, beat Brazil's Tomaz Bellucci 6-3, 6-4 while 13th seed Radek Stepanek stopped German Andreas Beck 7-5, 6-4. In other matches, Roland Garros finalist Robin Soderling of Sweden beat Romanian Victor Hanescu 6-3, 6-4. French 11th seed Gael Monfils will face Australian Lleyton Hewitt after beating compatriot Paul-Henri Mathieu 6-2, 6-2.

In first-round play, Hewitt advanced 6-2, 6-4 into the second round of the Shanghai Masters over John Isner with the Australian's eyes firmly fixed three months into the future. Hewitt, competing in Shanghai for the first time since winning the season-ending Masters Cup in the city in 2002, held the normally powerful American Isner to a mere five aces, breaking three times. The 28-year-old Australian has lifted his ranking from outside the Top 100 early in the year to its current 23rd.

Japan Open

OSAKA: Defending champion Caroline Wozniacki of Denmark launched her campaign in style by beating Japan's Ayumi Morita in the first round of the Japan Open women's tennis on Tuesday.

The 19-year-old Dane, ranked sixth after her runner-up finish at the US Open, saved two out of two break points while she won three out of three break chances to score a 6-4, 6-1 win. In the second round, she will face Katie O'Brien of Britain, who beat American Alexa Glatch on Monday.

Former champion Jill Craybas of the United States, whose only WTA title came in the 2002 Japan Open, edged past four-time champion Kimiko Date-Krumm 6-2, 2-6, 6-4. Marion Bartoli of France, the second seed and 2006 champion, outclassed Galina Voskoboeva of Kazakhstan 6-3, 7-5.

In other action, Taiwan's Chang Kai-chen, who shocked then world number one Dinara Safina of Russia in Tokyo two weeks ago, defeated Tamarine Tanasugarn of Thailand 7-5, 6-1. Japan's Kurumi Nara earned a place against Bartoli by beating Chanelle Scheepers of South Africa 7-6 (7/5), 4-6, 6-2, while third seed Samantha Stosur of Australia beat Alexandra Panova of Russia 6-2, 6-4.