Former world No 15 Kaia Kanepi caused a huge upset on the first day of the US Open when she knocked out world No 1 Simona Halep 6-2, 6-4.

A year after making her sixth career appearance in a Grand Slam quarter-final, Kanepi blasted 26 winners to Halep’s nine over the course of the upset and broke serve five times for her second career victory over the Romanian in one hour, 16 minutes.

Kanepi got off to a blistering start, winning five of the opening six games to take a substantial lead in the opening set. Halep could not recover and surrendered the first set 6-2.

Kanepi carried her momentum into the second, securing a double-break to take a 3-0 lead. Halep got those breaks of serve back in the fourth and eighth games to level the set at 4-4, but she could not hold serve in the ninth.

Kanepi served out the match in the next game and sent the world’s top-ranked player packing on the first day of the year’s final major.

South Africa’s Kevin Anderson almost suffered the same fate. The Wimbledon finalist rallied back from 2-1 down, to overcome American Ryan Harrison in five sets.

It took the South African four hours and 18 minutes to reach the next round with a 7-6 (4), 5-7, 4-6, 6-3, 6-4 victory.

What Anderson had to say after his victory:

Other selected men’s results:

Andy Murray defeated James Duckworth 6-7 (5), 6-3, 7-5, 6-3
Stan Wawrinka defeated Grigor Dimitrov 6-3, 6-2, 7-5
John Isner defeated Bradley Klahn 7-6 (3), 6-3, 6-4
Juan-Martin del Potro defeated Donald Young 6-0, 6-3, 6-4

Other selected women’s results:

Serena Williams defeated Magda Linette 6-4, 6-0
Karolina Pliskova defeated Zarina Diyas 6-4, 7-6 (4)
Sloane Stephens defeated Evgeniya Rodina 6-1, 7-5
Garbine Muguruza defeated Shuai Zhang 6-3, 6-0

Photo: USopen.org