Fourth seed out of Australian Open 2017 after shock loss to Shelby Rogers
The match began with the pair exchanging in long rallies, working each other from side to side, with the Romanian putting an abundance of pressure on the Rogers serve early.
However, it was the American who drew first blood, breaking Halep in a mammoth sixth game that went to deuce six times before Rogers converted her third break point opportunity. She would consolidate strongly in the next game to hold a commanding 5-2
Halep held in another tough service game, but was powerless to stop Rogers claiming the first set 6-3 in 46 minutes.
Halep called the trainer after the first set with a lower leg complaint, but it seemed to do little as the American broke in the third game before holding to take move closer to the finish line.
The American began to outmuscle the world No.4 as she broke again to seal the match and what will be one of the biggest upsets of the opening day.
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Rogers was supreme in the tight moments, saving the only break point she faced and also winning 66 per cent of her second serve points, along with the 26 winners that she clubbed.
She will meet the winner of Australian Ash Barty and German Annika Beck in the second round.