INDIAN WELLS, CA, USA – World No.5 Simona Halep had begun to find her form in the opening set of her match against unseeded and looming Barbora Strycova at the BNP Paribas Open, but after winning five games in a row, the Czech called the trainer to court for an upper respiratory illness, ultimately sending Halep into the quarterfinals, 6-3, 1-0, ret.

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The pair had split their prior two meetings and Strycova, fresh off a run to the finals of the Dubai Duty Free Tennis Championships, initially took advantage of an out-of-sorts Halep, who was playing her first day session match on Stadium Court 3.

Halep, however, has been in stellar form throughout her opening round matches, and with a little help from coach Darren Cahill, the former World No.2 slowly shifted into turbo as Strycova became overcome, calling the trainer on the set break.

“I feel sorry for her, being sick,” she said during her on-court interview. “I know how it is, and it’s tough to continue to play the match. It was a good start for me; I played a good first set, but the conditions are really difficult because I played two matches in the cold weather, and now it’s hot. I tried everything to keep things going in the right away, so I’m happy to be into the quarterfinals.

“I adjusted my game very well, just wanted to make fewer mistakes and keep the ball into the court. I moved better than I did in the beginning of the match, and I’m looking forward to the next one, where I hope to play better.”

Awaiting Halep in the quarterfinals will be the winner of World No.1 Serena Williams and qualifier Kateryna Bondarenko; the 2014 French Open finalist was set to play Williams in last year’s semifinal before the American was forced to pull out with a knee injury.

“I would like to play against her; I’m looking forward to it, and I know she’s the best player in the world, so I have nothing to lose. I want just to go and fight for my chance – I know that I have a chance.

“I will go with confidence, positivity and just fighting for the match.”