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MELBOURNE, Feb 10 (Reuters) - Two-time Wimbledon champion Petra Kvitova had no excuses for her second-round exit at the Australian Open on Wednesday, refusing to blame the mandatory two-week quarantine for her rusty display in a 6-4 1-6 6-1 defeat by Romanian Sorana Cirstea.
Kvitova recovered well after losing the opening set but her efforts were undone by untidiness, the Czech finishing with 44 unforced errors and seven double faults.
"I think this match wasn't really about the quarantine or being just practicing differently," said Kvitova, who was allowed outside her hotel room for five hours a day to train.
"It's a little painful and I'm really disappointing about my loss. I didn't really bring the best tennis today. It's really hurting.
"I should have take the first set when I was leading a break... and it would be different story."
Ninth seed Kvitova jumped out to a 2-0 lead but could not keep a lid on her errors as Cirstea converted each of her three breakpoint opportunities to claim the opening set.
Kvitova, who finished runner-up at Melbourne Park two years ago, showed glimpses of her powerful ball-striking as she raced to a 4-0 lead in the second set before levelling the match when Cirstea handed her a third break with a tame double fault.
Cirstea, however, turned the tables on the Czech in the final set and claimed victory on her third match point with Kvitova hitting a forehand long.
Having secured her first win over a top-10 opponent at a Grand Slam in nine years, Cirstea will next face 19th seed Marketa Vondrousova in a bid to match her best result at the Australian Open -- a fourth round showing from four years ago.
"I was one of the few in hard quarantine. I think it's impressive to come out of 15 days without hitting a ball and competing the way I did today, I wasn't expecting it," Cirstea said.