Radwanska wins opener in Tokyo

Agnieszka Radwanska was a 6-1, 6-1 winner against Japan's Misaki Doi on Sunday to cruise into the second round at the $2.05 million Toray Pan Pacific Open.

The Polish Radwanska, seeded ninth, needed only 66 minutes to complete the rout on the hardcourts at Ariake Colosseum. She will next face German Angelique Kerber, a 6-1, 6-0 winner against Serb Bojana Jovanovski.

Other first-round winners Sunday included 11th-seeded Russian Anastasia Pavlyuchenkova and 16th-seeded Shahar Peer of Israel.

Pavlyuchenkova, coming off her quarterfinal appearance at the U.S. Open, rolled to a 6-4, 6-3 win over Dutch left-hander Arantxa Rus. Peer battled back to beat Czech wildcard Kristyna Pliskova 4-6, 7-5, 6-1.

Japan's Ayumi Morita, Romanian Irina-Camelia Begu, Hungarian Greta Arn, Thailand's Tamarine Tanasugarn and Great Britain's Laura Robson also recorded first-round wins Sunday.

Czech Barbora Zahlavova Strycova moved into the second round when her opponent, Latvian Anastasija Sevastova, retired with a right hip injury. Zahlavova Strycova was up 7-6 (7-2), 4-1 at the time Sevastova pulled out.

This week's top seeds are reigning champion Caroline Wozniacki, former world No. 1 Maria Sharapova, Victoria Azarenka, Vera Zvonareva, Wimbledon champion Petra Kvitova, and U.S. Open titlist Samantha Stosur. The current world No. 1 Wozniacki beat since-retired Russian star Elena Dementieva in last year's Pan Pacific finale.

The 2011 Pan Pacific champ will collect $360,000.