No. 1 seed Simona Halep is overpowered by 44th-ranked Kaia Kanepi in the U.S. Open’s first round

The first upset of the U.S. Open was a big one. No. 1 women’s seed Simona Halep of Romania, who won the French Open title a few months ago, was overpowered by hard-hitting Kaia Kanepi of Estonia, who earned a 6-2, 6-4 victory in their first-round match at hot, humid Louis Armstrong Stadium on Monday.

It’s the second straight year that Halep was ousted in the first round at Flushing Meadow. She was the No. 2 seed when she lost to Maria Sharapova last year, but Halep has held the No. 1 ranking for the last 26 weeks. Because of the points system that determines the rankings, she is assured of holding the top spot despite her early loss here.

It marked the first time in the Open era — which began in 1968 — that the No. 1 seed has lost in the first round at the U.S. Open. It had happened five times in the other three Grand Slam events. The last No. 1-seeded woman to win the U.S. Open was Serena Williams in 2014.

Kanepi, ranked No. 44 in the world, reached the quarterfinals here last year but hadn’t done much of note this year and was 27-13 in match play before she defeated Halep. For perspective: She lost in the first round at the French Open, while Halep won that tournament to earn her first career Grand Slam title.

Kanepi was impressive in the first set, going up two breaks to take a 4-1 lead and finishing off the set by winning at love. She wore down a little bit in the second set, when Halep broke to cut Kanepi’s lead to 3-1. Halep held for 3-2 and although Kanepi began to miss shots, she gutted out the rest of the match and finished with 26 winners, to nine for Halep.