US Open: Ukrainian qualifer Daria Snigur upsets two-time Grand Slam champion Simona Halep in emotional first round victory

Ukrainian qualifier Daria Snigur has produced the performance of her career to upset twice Grand Slam winner Simona Halep 6-2 0-6 6-4 in the first round of the US Open.

Snigur, 20, showed poise beyond her years to break Halep in the opening game and again in the third, as she capitalised on a mounting number of unforced errors from the Romanian.

Her form completely fell apart in the second set, as Halep stormed through six games in 24 minutes to roars of approval from the crowd at Lois Armstrong Stadium.

But Halep, who won the Canadian Open title for the third time earlier this month, before pulling out of Cincinnati with injury, failed to maintain that momentum, as she dropped her serve in the first and fifth games.

Coco Gauff celebrates a point at the US Open
Coco Gauff celebrates a point at the US Open. Photo credit: Getty Images

Haelp, 30, broke Snigur in the eighth game to stay alive and fended off two matchpoints in the next game, but Snigur kept her nerve to seal victory before bursting into tears. She then formed a heart shape with her hands around the Ukrainian ribbon pinned to her shirt.

"I'm very, very, very nervous, but I tried to do my best," she said, her voice shaking. "For Ukraine, for my family... I want to say thank you all." 

American Coco Gauff eased into the second round with a comfortable 6-2 6-3 victory over France's Leolia Jeanjean.

Gauff, the 12th seed and home favourite, had the crowd at Arthur Ashe Stadium firmly behind her, as she wrapped up the match in 79 minutes on the back of a strong first serve.

"I'm super excited, because this is my first win on Ashe," she said. "I think this is my fourth match here on this court and it's my first win."

The 18-year-old, who was French Open runner-up earlier this year, fired eight aces and lost only two points on her first serve.

Meanwhile, former US Open champion Bianca Andreescu has had to apologise to sponsor Nike for an oncourt outburst, after her choice of wardrobe for her first-round match landed her in a spot of bother amid windy conditions.

Andreescu was out on the Grandstand court to play Harmony Tan, but the winds at the open arena kept blowing her skirt up and affecting her shots, forcing the 22-year-old to approach the chair umpire and request an additional bathroom break to change.

"Will this not count as one of my changeovers?" she told the umpire. "I mean it's not my fault, it's Nike's fault.

Bianca Andreescu in action at the US Open
Bianca Andreescu in action at the US Open. Photo credit: Getty Images

"This dress is so, so bad... I need to go [change], this is really bad."

Andreescu returned, wearing a white Nike tank top and skirt, to eventually beat Tan 6-0 3-6 6-1.

"It was just bothering me on some forehands," she said afterwards. "I just felt like it was kind of coming up a bit.

"Obviously the wind didn't help, but I meant no disrespect with what I said to the umpire. I was trying to convince him to not take away that washroom break, because I know we only get two.

"He was very nice to say it was totally OK. I could have definitely used a different choice of wording, so I apologise to anyone I disrespected.

"I love Nike and I hope I can be with them for the rest of my life!"

Andreescu will next play Beatriz Haddad Maia in the second round. 

Reuters