Simona Halep became the first No. 1 seed to lose in the first round of the US Open in the 50 years of the Open Era, falling to Kaia Kanepi 6-2, 6-4 in straight sets.

Simona Halep US Open
World No. 1 Simona Halep lost her first round match to Kaia Kanepi, the second straight year Halep has lost in the opening round at the US Open. (Image: Getty)

It was the second straight year with a first-round loss for the Romanian who won her first Grand Slam title earlier this year when she captured the French Open championship.

Aggressive Play Pays Off for Kanepi

Heading into the match, few expected a walk in the park for Halep. Kanepi has been ranked as high as 15th in the world, and has made six Grand Slam quarterfinals appearances in her career.

Still, the current world No. 44 was a severe underdog. But an aggressive, powerful playing style allowed the Estonian to win five of the first six games, after which she never looked back.

She has been playing really well in US lately, so I thought I just have to be aggressive and try to stay calm, Kanepi said after the match. I can be aggressive when I want to, because she defends a lot, but I have time to be aggressive.

New York Jitters?

The loss continued a trend of first round struggles for Halep, who has one of the most erratic records of any top-ranked player in recent memory. She is only 28-12 in the first round at Grand Slam events, a surprisingly poor record for a player who has also made the quarterfinals 11 times at majors.

For me, its more difficult in the first rounds, Halep said after the loss. Because Im more emotional. Thats why I need a good start.

Halep had been playing well in the hard-court season, making the finals in Cincinnati and Montreal, two of the largest events leading into the US Open. That led Halep to suggest that maybe she does have particular trouble in New York.

Maybe the noise in the crowd. The city is busy, she said after the match. Im a quiet person, so maybe I like the smaller places.

The loss was especially devastating because it came at a time when Halep seemed to be growing into a true star on tour. While she had reached the No. 1 ranking in the world, she noted that it wasnt quite the same before her win at Roland Garros earlier this year.

Inside myself something changed. Im more relaxed, she told reporters on Friday. Always I say number one in the world without a Grand Slam, you are not a real number one. After the French Open, I really started to believe that Im a real number one.

While the first round loss means Halep will only pick up 10 rankings points this week, her lead on the field is so large she is more than 2,000 points ahead of world No. 2 Carolina Wozniacki hat she will keep her No. 1 ranking regardless of what happens in the rest of the tournament.

The elimination of Halep has positioned Serena Williams as the clear favorite to win her seventh US Open title. Williams, who won her first round match 6-4, 6-0 over Magda Linette, is now listed as the 4/1 favorite to win the tournament by William Hill. Shes followed by Angelique Kerber (7/1), Sloane Stephens (7/1), and Elina Svitolina (8/1).