Monday August 31st, 2015

Serbia's Ana Ivanovic was upset in the first round of the U.S. Open on Monday. 

Ivanovic, the No. 7 seed in the women's bracket, was defeated 6-3, 3-6, 6-3 by Slovakia's Dominika Cibulkova. 

It's the first big upset of the tournament, with most ranked players on the women's side yet to begin their matches. 

Ivanovic, a former No. 1 ranked player, was in search of her second Grand Slam title. Her only major win came in the 2008 French Open. She was the runner-up at Roland Garros in 2007, and in the Australian Open in 2008.

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Ivanovic's furthest run in the U.S. Open came in 2012, when she made the quarterfinals. 

No. 1 seed Serena Williams, the tournament favorite, will kick off her quest for a calendar Grand Slam on Monday night. 

- Rohan Nadkarni

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