Both players entered the game under a cloud of injury: Halep was seeking his first win since August in his second appearance in the tournament while Kanepi was playing his first match since the second week at Flushing Meadows.
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Kanepi defeated 40 winners as he sought the frustrated proposal, and a third career victory against reigning World No.1, but was undone by more than 60 unforced errors over two hours and 11 minutes.
She remained in touch in the final set as neither side faced a break point in the first five games of the decision, but last year's runner-up Halep increased their level during the final stages of the game.
The head of the team won the last four games to avoid the turn, and advanced to the second round against another dangerous wave: the recent international champion of Hobart, Sonya Kenin.
More to come …