NEW YORK, NY, USA – No.23 seed Donna Vekic showed incredible mental fortitude to save a match point against Julia Goerges and qualify for the quarterfinals of the US Open for the first time after a marathon 6-7(5), 7-5, 6-3 victory that lasted two hours and 45 minutes on Louis Armstrong.

Vekic will play her first last-eight match at a major after progressing to face Belinda Bencic the hard way against Goerges, who herself had battled back from the very brink against Natalia Vikhlyantseva in the first round.

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In order to do so, she had to weather a remarkable storm of serving, with Goerges delivering 21 aces – the most in a women’s singles match since 1998.

The 30-year-old, who had won all three previous meetings between the pair, was dominant in the opening two sets but stumbled when seeking to close the match out, sparking a stunning recovery from her opponent that had looked unlikely only moments before.

“I don’t know how I won this match. She served for it, she had match points. I kept fighting and believing I could win,” Vekic admitted.

“I think when the matches are this close, even if you're match points down, you have to believe that you can win. I was really going out there, when she was serving for 5-4, I was really thinking I could win this game and try to turn the match around.

“I was just trying to get a return in the court. She served amazing today. I felt confident in the rallies and I felt that if I got the ball in, I’d have a good chance.”

It was the German who struck out the better of the two players, hitting the ball crisply and powerfully off both wings to race into a 3-0 lead courtesy of a backhand down the line on the first break point of the match.

Serve would go on to dominate the opening set and indeed the only two break points that were crafted were taken. Goerges, particularly, hit a strong early rhythm as her ace count rapidly escalated. A brief lapse midway through the set saw her broken but she did not concede another point off her own delivery until the tiebreak.

Vekic, meanwhile, lost only four points on her first serve before the inevitable breaker was required to decide the opener.

Goerges’ ball striking had blown a little cold in the latter part of the set, but she rediscovered her best in deciding game. After initially slipping behind, a superb volley and an equally accomplished pass, which Vekic described as "unreal", carried her to set point, at which she delivered the type of one-two punch on serve that was the motif of much of her match.

She maintained this impressive momentum into the second, forging another break after a couple of big winners, then chalking up a hold thanks to three successive aces before her opponent was able to get on the board.

A fine dropshot highlighted the confidence that she was oozing, although she failed to convert a break point for the first time in the match on Vekic’s next service game, despite bringing up 0-30 thanks to a blistering forehand return that found a seemingly impossible angle.

She remained relentless on serve until she seeking to seal the match, at which point she threw in a game that included three double faults and a time violation as Vekic drew level out of the blue then went on to grind out the set.

With Goerges apparently starting to fade, Vekic brought up two break points in the sixth game of the decider with a super backhand down the line but saw them nullified by a big winner and an equally sizeable ace as the danger passed.

She made no mistake when given another opportunity, forging ahead of the first time in the match at 5-3, with an untimely double fault handing her the break.

There was more drama to come, however, as Goerges reprised her best to fashion two break points when all seemed lost, but Vekic saw them off to seal a gutsy victory.

"I definitely had the momentum on my side after second set," she said. "I knew she was going to be thinking about her match point. I had few chances to break her earlier in the third set, but she was just serving amazing today. But I'm happy that I could break her and then serve it out."