Ana Ivanovic upset in first round of U.S. Open

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

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