Ana Ivanovic upset by Ayumi Morita at Pattaya Open

Ana Ivanovic lost in the fourth round of the Australian Open to Agnieszka Radwanska.

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PATTAYA, Thailand (AP) -- Ayumi Morita of Japan knocked top-seed Ana Ivanovic out of the Pattaya Open on Thursday, beating the Serb 6-3, 5-7, 6-3.

After Wednesday was rained out, Morita completed her win over Ivanovic in a match suspended in the third set Tuesday.

Morita returned later to beat Kimiko Date-Krumm 4-6, 6-4, 6-1 for a place in the quarterfinals.

Defending champion Daniela Hantuchova retired from her match, while trailing Nina Bratchikova of Russia 6-2, 3-0 in the second round.

Maria Kirilenko, Sorana Cirstea, Sabine Lisicki, Elena Vesnina, Anastasija Sevastova and Marina Erakovic also reached the quarterfinals.

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