EASTBOURNE, England, June 18 (UPI) --
Top-seeded Agnieszka Radwanska
of Poland was ushered to a first-round exit by American qualifier Jamie Hampton Tuesday in an Aegon International upset.
Radwanska, the 4th-ranked former Wimbledon runner-up, tumbled to the 23-year-old American 7-6 (7-2), 6-2 at Devonshire Park.
Also falling in a surprise result Tuesday was eighth-seeded Russian Nadia Petrova, who was upended 6-2, 6-3 by former U.S. Open champion Samantha Stosur.
Second-seeded Li Na of China, however, safely made it into the second round, dispatching France's Alize Cornet 6-2, 6-4.
Also notching opening-round victories Tuesday were third-seeded Angelique Kerber, who bested Romanian Sorana Cirstea 6-4, 6-4, and No. 4 Petra Kvitova, who drilled Romanian Monica Niculescu 6-4, 6-1.
Fifth-seeded Caroline Wozniacki of Denmark advanced when defending Eastbourne champion Tamira Paszek retired while trailing 6-2, 2-2.
Wild card Elena Baltacha, fellow Briton Laura Robson and Russia's Ekaterina Makarova also moved on with victories.