Sam Stosur of Australia in action against Christina McHale of USA during the Mutua Madrilena Madrid Open at the Caja Magica on May 7, 2012 in Madrid, Spain.
(May 6, 2012 – Source: Mike Hewitt/Getty Images Europe)

WIMBLEDON, England (AP) – Third-seeded Agnieszka Radwanska and Grand Slam champions Sam Stosur and Li Na won in straights sets Monday to move into the second round of Wimbledon on a dry opening day at the All England Club.

Radwanska, who has twice reached the quarterfinals at Wimbledon, beat Magdalena Rybarikova of Slovakia 6-3, 6-3 in the day’s first match on Court 2.

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Rybarikova took an injury time-out after her left leg gave way and she fell behind the baseline while trailing 2-1 in the second set. After treatment, she returned to the match with her leg heavily wrapped and did not seem troubled the rest of the way.

The fifth-seeded Stosur, the 2011 U.S. Open champion, cruised to a 6-1, 6-3 win over Carla Suarez-Navarro of Spain. The hard-hitting Australian has traditionally struggled on the grass at Wimbledon, losing in the first round in the past two years and never advancing past the third round, but she was always in command Monday.

Li, the 2011 French Open champion who is seeded No. 11, swept past Ksenia Pervak of Russia 6-3, 6-1. No. 15 Sabine Lisicki of Germany, a semifinalist last year, beat Petra Martic of Croatia 6-4, 6-2.

The first seed eliminated was No. 16 Flavia Pennetta, who fell 6-4, 6-3 to fellow Italian Camila Giorgi.

Play began right on time at 6:30 a.m. ET on the outside courts under cloudy skies but without any threat of the rain that has soaked London and parts of Britain for much of the past few weeks. Temperatures reached 72 degrees.

First up on Centre Court was top-ranked defending champion Novak Djokovic, who was facing former No. 1 Juan Carlos Ferrero. Six-time champion Roger Federer was to play Albert Ramos of Spain on Court 1 — the first time since 2003 that he wasn’t assigned to Centre Court for the opening round.

Also on the schedule on Day 1 of the championships will be defending champion Novak Djokovic, and Maria Sharapova and Venus Williams.