American Coco Vandeweghe upsets Garbine Muguruza to reach Australian Open semifinals

MELBOURNE — American Coco Vandeweghe has become the upset queen of the Australian Open after blasting her way into a first career Grand Slam semifinal on Tuesday by upsetting reigning French Open champion Garbine Muguruza 6-4,  6-0.

"I really wasn’t feeling all that great out there," said Vandeweghe, who only capitalized on one of nine break point opportunities in the first set. "I was kind of nervous. I just tried to play my best, play within myself, keep my patterns."

The 25-year-old Vandeweghe was nearly flawless once she settled into the second set, winning 13 of 19 points played on her own serve, and won a perfect nine of nine points on her first serve.

"Once I got rolling in the second it was like a freight train and you couldn’t stop it," Vandeweghe said laughing.

The 35th-ranked Vandeweghe pulled off the biggest upset of the tournament when she ousted world No. 1 Angelique Kerber 6-2, 6-3 in the fourth round on Sunday. She now has 10 career wins over top 10 ranked opponents.

Vandeweghe will play Venus Williams in an all-American semifinal. Williams earned her semifinal slot with a 6-4, 7-6 (7-3) quarterfinal win over 24th-seeded Anastasia Pavlyuchenkova of Russia.

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"Honored to play as great a champion as Venus and someone I grew up watching," said Vandeweghe, who remembered back to trying to get an autograph from Williams when she was a child.

This was Vandeweghe’s second showing in a Grand Slam quarterfinal having reached that round at Wimbledon in 2015 where she fell to Maria Sharapova.

Vandeweghe makes 2017 the third consecutive year an unseeded player has reached the women's semifinals at the Australian Open. In 2015, American Madison Keys did the deed, and last year Australian-born British citizen Johanna Konta reached the final four. Neither Keys or Konta moved onto the final.

This marked the first time that the seventh-seeded Muguruza was a quarterfinalist at the Australian Open. Since her win at the French Open, this was her best showing at a Grand Slam, having lost in the second round at Wimbledon and U.S. Open last year.

Always touted as an incredible athlete, Vandeweghe’s most notable issue has been consistency. She tends to play top-flight tennis one tournament, as she is doing here at Melbourne Park, but then goes on to have periods of struggle afterwards.

Vandeweghe comes from a famous American sporting family. Of her maternal Vandeweghe relatives, late grandfather Ernie and uncle Kiki were NBA stars, and Kiki Vandeweghe currently is the NBA vice president of basketball operations. Her mother, Tauna Vandeweghe, was an Olympic swimmer.

There was also the fashion and beauty side to her family. Her late maternal grandmother, Colleen Kay Hutchins, was Miss America 1952 — Coco's legal first name is Colleen. Her paternal grandmother, Theresa Mall Mullarkey, was a Ford Agency model with a Harper’s Bazaar cover before becoming Chancellor of CW Post at Long Island University campus.

Follow Sandra Harwitt on Twitter @TennisGrapevine.