NEW YORK, Aug 31 (Reuters) - Jelena Dokic was unable to shake off the rust of a two-month layoff and lost to Belgian Kirsten Flipkens 6-3 6-4 in the first round of the U.S. Open on Monday.
Dokic had not played competitively since a first-round loss at Wimbledon due to a debilitating bout of mononucleosis.
The 26-year-old Australian had 41 unforced errors, nine double faults and no aces while losing to the 93rd-ranked Flipkens in 66 minutes.
"It's tough because I think I could have had a much better year," said the 83rd-ranked Dokic, who opened 2009 with a run to the Australian Open quarter-finals.
"I was still playing well around Miami (in March) and the French Open. After that, things just kind of went downhill.
"I was fit and I was playing well. When I got sick at Eastbourne (in mid-June) and then Wimbledon, things really started going downhill. It's just so unlucky."
Dokic said she was determined to rebound and play well the rest of the year.
"It counts how many times you get up, not how many times you fall down," she said.
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