Top seed Angelique Kerber crashed out of the Qatar Open Tuesday, losing her first tournament match since winning the Australian Open last month. An out-of-sorts Kerber lost in straight sets 7-5, 6-1 to China's Zheng Saisai, who is ranked 71 places below the world No. 2. In a lackluster performance, the German lost her serve six times throughout the match, hit 38 unforced errors — Saisai hit only eight — and was beaten in just one hour and eighteen minutes as her opponent dominated. The second set took just 28 minutes as Kerber's game collapsed. Kerber, who has not played any singles tournaments since winning against Serena Williams in Melbourne on Jan. 30, grew increasingly exasperated with her form and at one point could be heard telling her coach Torben Beltz that she was tired and had no energy. Saisai will play Canada's Eugenie Bouchard in the third round. Bouchard beat the Czech Republic's Denisa Allertova 7-6 (7-0), 7-5 as she recovers from her injury-strewn 2015. Also through Tuesday was Petra Kvitova who won 7-6 (7-2), 6-4 against Czech compatriot Barbara Strycova. Earlier, the tournament's No. 3 seed Agnieszka Radwanska won 6-4, 6-4 against Kateryna Bondarenko from Ukraine. "Obviously it was hard conditions, but I won," said Radwanska afterwards. "That's the most important thing. The first matches are always very tricky, especially the different conditions everywhere, and here in Doha as well. We used to it (being) always a bit windy and can be very tough." Also through is Petra Kvitova who won 7-6 (7-2), 6-4 against Czech compatriot Barbora Strycova. In other results: Andrea Petkovic of Germany edged Margarita Gasparyan of Russia 6-3, 6-3; Carla Suárez of Spain beat Donna Vekic of Croatia 7-6 (7-5), 6-4; and Tímea Babos downed Sara Errani 6-4, 6-1. On Monday, former No. 1 Caroline Wozniacki worked overtime to avoid a first-up loss for the third time in her last four tournaments. Wozniacki, whose ranking has dropped to No. 22, overcame Croatian qualifier Ana Konjuh 4-6, 6-3, 7-5. After dropping the first set, Wozniacki seemed in control when she won the second and raced to 5-2 in the third. But Konjuh went for risky shots and was rewarded with success as she clawed back to 5-5. She went on to save eight match points before finally succumbing. "A win is a win. I am going to take it and I am happy," Wozniacki said. "It's the first match and you just want to get going. I wasn't hitting it well." In the second round, she will meet Australia's Daria Gavrilova, who beat Japan's Misaki Doi 6-1, 6-1. US Open champion Roberta Vinci celebrated her rise into the top 10 by putting away Lesia Tsurenko of Ukraine 6-2, 6-1, and Italian compatriot Sara Errani, fresh off winning the Dubai Championships Saturday, defeated Tsvetana Pironkova of Bulgaria 1-6, 7-5, 6-3. Another former US Open champ, Svetlana Kuznetsova, beat Julia Goerges of Germany 6-3, 6-3, while the only upset on the day was 15th-seeded Elina Svitolina of Ukraine falling to Denisa Allertova of the Czech Republic 7-5, 6-4. The top eight seeds, led by Australian Open champ Angelique Kerber of Germany, have a bye to the second round. — Agencies